-NOTE: This file is automatically generated from the files `news0.texi'
-and `news.texi'. `NEWS' is *not* a source file, although it is
-normally included within source distributions.
+*Note:* This file is automatically generated from the files
+`news0.texi' and `news.texi'. `NEWS' is *not* a source file, although
+it is normally included within source distributions.
- This file lists recent changes to the GNU Fortran compiler.
-Copyright (C) 1995-1999 Free Software Foundation, Inc. You may copy,
-distribute, and modify it freely as long as you preserve this copyright
-notice and permission notice.
+ This file lists news about the EGCS-1.2 version (and some other
+versions) of the GNU Fortran compiler. Copyright (C) 1995-1999 Free
+Software Foundation, Inc. You may copy, distribute, and modify it
+freely as long as you preserve this copyright notice and permission
+notice.
News About GNU Fortran
**********************
getting a complete picture of what a particular `egcs' version contains
somewhat more difficult.
-In `egcs' 1.2:
-==============
+ *Warning:* The information below is still under development, and
+might not accurately reflect the `g77' code base of which it is a part.
+Efforts are made to keep it somewhat up-to-date, but they are
+particularly concentrated on any version of this information that is
+distributed as part of a *released* `g77'.
- * Fix `g77' so it no longer crashes when compiling I/O statements
+ In particular, while this information is intended to apply to the
+EGCS-1.2 version of `g77', only an official *release* of that version
+is expected to contain documentation that is most consistent with the
+`g77' product in that version.
+
+ Nevertheless, information on *previous* releases of `g77', below, is
+likely to be more up-to-date and accurate than the equivalent
+information that accompanied those releases, assuming the last-updated
+date of the information below is later than the dates of those releases.
+
+ That's due to attempts to keep this development version of news
+about previous `g77' versions up-to-date.
+
+ An online, "live" version of this document (derived directly from
+the mainline, development version of `g77' within `egcs') is available
+at `http://egcs.cygnus.com/onlinedocs/g77_news.html'.
+
+ The following information was last updated on 1999-04-23:
+
+In `egcs' 1.2 (versus 1.1.2):
+=============================
+
+ 1. `g77' no longer generates bad code for assignments, or other
+ conversions, of `REAL' or `COMPLEX' constant expressions to type
+ `INTEGER(KIND=2)' (often referred to as `INTEGER*8').
+
+ For example, `INTEGER*8 J; J = 4E10' now works as documented.
+
+ 2. Fix `g77' so it no longer crashes when compiling I/O statements
using keywords that define `INTEGER' values, such as `IOSTAT=J',
where J is other than default `INTEGER' (such as `INTEGER*2').
Instead, it issues a diagnostic.
- * The `-ax' option is now obeyed when compiling Fortran programs.
+ 3. Fix `g77' so it properly handles `DATA A/RPT*VAL/', where RPT is
+ not default `INTEGER', such as `INTEGER*2', instead of producing a
+ spurious diagnostic.
+
+ 4. The `-ax' option is now obeyed when compiling Fortran programs.
(It is passed to the `f771' driver.)
+ * The new `-fsubscript-check' option causes `g77' to compile
+ run-time bounds checks of array subscripts, as well as of
+ substring start and end points.
+
+ The current implementation uses the `libf2c' library routine
+ `s_rnge' to print the diagnostic. Since a future version of `g77'
+ might use a different implementation, use the new
+ `-ff2c-subscript-check' option if your application requires use of
+ `s_rnge' or a compile-time diagnostic.
+
* Source file names with the suffixes `.FOR' and `.FPP' now are
recognized by `g77' as if they ended in `.for' and `.fpp',
respectively.
- * `g77' now warns about a reference to a function when the
+ * `g77' now warns about a reference to an intrinsic that has an
+ interface that is not Year 2000 (Y2K) compliant. Also, the
+ `libg2c' has been changed to increase the likelihood of catching
+ references to the implementations of these intrinsics using the
+ `EXTERNAL' mechanism (which would avoid the new warnings).
+
+ 5. `g77' now warns about a reference to a function when the
corresponding *subsequent* function program unit disagrees with
the reference concerning the type of the function.
- * Improve documentation and indexing, including information on Year
- 2000 (Y2K) compliance.
+ * `-fno-emulate-complex' is now the default option. This should
+ result in improved performance of code that uses the `COMPLEX'
+ data type.
+
+ * The `-malign-double' option now reliably aligns *all*
+ double-precision variables and arrays on Intel x86 targets.
+
+ 6. Even without the `-malign-double' option, `g77' reliably aligns
+ local double-precision variables that are not in `EQUIVALENCE'
+ areas and not `SAVE''d.
+
+ 7. A substantial portion of the `g77' front end's code-generation
+ component was rewritten. It now generates code using facilities
+ more robustly supported by the `gcc' back end. One effect of this
+ rewrite is that some codes no longer produce a spurious "label LAB
+ used before containing binding contour" message.
+
+ * Support for the `-fugly' option has been removed.
+
+ 8. Improve documentation and indexing, including information on Year
+ 2000 (Y2K) compliance, and providing more information on internals
+ of the front end.
+
+ 9. Upgrade to `libf2c' as of 1999-03-17.
In 0.5.24 and `egcs' 1.1.2 (versus 0.5.23 and 1.1.1):
=====================================================
+ * Fix the `IDate' intrinsic (VXT) (in `libg2c') so the returned year
+ is in the documented, non-Y2K-compliant range of 0-99, instead of
+ being returned as 100 in the year 2000.
+
* Fix the `Date_and_Time' intrinsic (in `libg2c') to return the
milliseconds value properly in VALUES(8).
In `egcs' 1.1 (versus 0.5.24):
==============================
- * Fix `g77' crash compiling code containing the construct
+ 10. Fix `g77' crash compiling code containing the construct
`CMPLX(0.)' or similar.
- * Fix `g77' crash (or apparently infinite run-time) when compiling
+ 11. Fix `g77' crash (or apparently infinite run-time) when compiling
certain complicated expressions involving `COMPLEX' arithmetic
(especially multiplication).
- * Fix a code-generation bug that afflicted Intel x86 targets when
+ 12. Fix a code-generation bug that afflicted Intel x86 targets when
`-O2' was specified compiling, for example, an old version of the
`DNRM2' routine.
In `egcs' 1.1 (versus `egcs' 1.0.3):
====================================
- * Fix bugs in the `libU77' intrinsic `HostNm' that wrote one byte
+ 13. Fix bugs in the `libU77' intrinsic `HostNm' that wrote one byte
beyond the end of its `CHARACTER' argument, and in the `libU77'
intrinsics `GMTime' and `LTime' that overwrote their arguments.
- * Assumed arrays with negative bounds (such as `REAL A(-1:*)') no
+ 14. Assumed arrays with negative bounds (such as `REAL A(-1:*)') no
longer elicit spurious diagnostics from `g77', even on systems
with pointers having different sizes than integers.
This bug is not known to have existed in any recent version of
`gcc'. It was introduced in an early release of `egcs'.
- * Valid combinations of `EXTERNAL', passing that external as a dummy
+ 15. Valid combinations of `EXTERNAL', passing that external as a dummy
argument without explicitly giving it a type, and, in a subsequent
program unit, referencing that external as an external function
with a different type no longer crash `g77'.
- * `CASE DEFAULT' no longer crashes `g77'.
+ 16. `CASE DEFAULT' no longer crashes `g77'.
- * The `-Wunused' option no longer issues a spurious warning about
+ 17. The `-Wunused' option no longer issues a spurious warning about
the "master" procedure generated by `g77' for procedures
containing `ENTRY' statements.
`libf2c' environment, even when `libf2c' (now `libg2c') is a
shared library.
- * `g77' no longer installs the `f77' command and `f77.1' man page in
+ 18. `g77' no longer installs the `f77' command and `f77.1' man page in
the `/usr' or `/usr/local' heirarchy, even if the `f77-install-ok'
file exists in the source or build directory. See the
installation documentation for more information.
- * `g77' no longer installs the `libf2c.a' library and `f2c.h'
+ 19. `g77' no longer installs the `libf2c.a' library and `f2c.h'
include file in the `/usr' or `/usr/local' heirarchy, even if the
`f2c-install-ok' or `f2c-exists-ok' files exist in the source or
build directory. See the installation documentation for more
information.
- * The `libf2c.a' library produced by `g77' has been renamed to
+ 20. The `libf2c.a' library produced by `g77' has been renamed to
`libg2c.a'. It is installed only in the `gcc' "private" directory
heirarchy, `gcc-lib'. This allows system administrators and users
to choose which version of the `libf2c' library from `netlib' they
wish to use on a case-by-case basis. See the installation
documentation for more information.
- * The `f2c.h' include (header) file produced by `g77' has been
+ 21. The `f2c.h' include (header) file produced by `g77' has been
renamed to `g2c.h'. It is installed only in the `gcc' "private"
directory heirarchy, `gcc-lib'. This allows system administrators
and users to choose which version of the include file from
than the one built and installed as part of the same `g77' version
is picked up.
- * During the configuration and build process, `g77' creates
+ 22. During the configuration and build process, `g77' creates
subdirectories it needs only as it needs them. Other cleaning up
of the configuration and build process has been performed as well.
- * `install-info' now used to update the directory of Info
+ 23. `install-info' now used to update the directory of Info
documentation to contain an entry for `g77' (during installation).
* Some diagnostics have been changed from warnings to errors, to
in the `OPEN', `INQUIRE', `READ', and `WRITE' statements, and
about truncations of various sorts of constants.
- * Improve compilation of `FORMAT' expressions so that a null byte is
+ 24. Improve compilation of `FORMAT' expressions so that a null byte is
appended to the last operand if it is a constant. This provides a
cleaner run-time diagnostic as provided by `libf2c' for statements
like `PRINT '(I1', 42'.
- * Improve documentation and indexing.
+ 25. Improve documentation and indexing.
- * The upgrade to `libf2c' as of 1998-06-18 should fix a variety of
+ 26. The upgrade to `libf2c' as of 1998-06-18 should fix a variety of
problems, including those involving some uses of the `T' format
specifier, and perhaps some build (porting) problems as well.
In 0.5.24 and `egcs' 1.1 (versus 0.5.23):
=========================================
- * `g77' no longer produces incorrect code and initial values for
+ 27. `g77' no longer produces incorrect code and initial values for
`EQUIVALENCE' and `COMMON' aggregates that, due to "unnatural"
ordering of members vis-a-vis their types, require initial padding.
- * `g77' no longer crashes when compiling code containing
+ 28. `g77' no longer crashes when compiling code containing
specification statements such as `INTEGER(KIND=7) PTR'.
- * `g77' no longer crashes when compiling code such as `J = SIGNAL(1,
+ 29. `g77' no longer crashes when compiling code such as `J = SIGNAL(1,
2)'.
* `g77' now treats `%LOC(EXPR)' and `LOC(EXPR)' as "ordinary"
* The F90 `System_Clock' intrinsic allows the optional arguments
(except for the `Count' argument) to be omitted.
- * Upgrade to `libf2c' as of 1998-06-18.
-
- * Improve documentation and indexing.
-
-In 0.5.23 (versus 0.5.22):
-==========================
-
- * This release contains several regressions against version 0.5.22
- of `g77', due to using the "vanilla" `gcc' back end instead of
- patching it to fix a few bugs and improve performance in a few
- cases.
-
- *Note Actual Bugs We Haven't Fixed Yet: Actual Bugs, available in
- plain-text format in `gcc/f/BUGS', for information on the known
- bugs in this version, including the regressions.
-
- Features that have been dropped from this version of `g77' due to
- their being implemented via `g77'-specific patches to the `gcc'
- back end in previous releases include:
-
- - Support for `__restrict__' keyword, the options
- `-fargument-alias', `-fargument-noalias', and
- `-fargument-noalias-global', and the corresponding
- alias-analysis code.
-
- (`egcs' has the alias-analysis code, but not the
- `__restrict__' keyword. `egcs' `g77' users benefit from the
- alias-analysis code despite the lack of the `__restrict__'
- keyword, which is a C-language construct.)
-
- - Support for the GNU compiler options `-fmove-all-movables',
- `-freduce-all-givs', and `-frerun-loop-opt'.
-
- (`egcs' supports these options. `g77' users of `egcs'
- benefit from them even if they are not explicitly specified,
- because the defaults are optimized for `g77' users.)
-
- - Support for the `-W' option warning about integer division by
- zero.
-
- - The Intel x86-specific option `-malign-double' applying to
- stack-allocated data as well as statically-allocate data.
-
- Note that the `gcc/f/gbe/' subdirectory has been removed from this
- distribution as a result of `g77' no longer including patches for
- the `gcc' back end.
-
- * Fix bugs in the `libU77' intrinsic `HostNm' that wrote one byte
- beyond the end of its `CHARACTER' argument, and in the `libU77'
- intrinsics `GMTime' and `LTime' that overwrote their arguments.
-
- * Support `gcc' version 2.8, and remove support for prior versions
- of `gcc'.
-
- * Remove support for the `--driver' option, as `g77' now does all
- the driving, just like `gcc'.
-
- * `CASE DEFAULT' no longer crashes `g77'.
-
- * Valid combinations of `EXTERNAL', passing that external as a dummy
- argument without explicitly giving it a type, and, in a subsequent
- program unit, referencing that external as an external function
- with a different type no longer crash `g77'.
-
- * `g77' no longer installs the `f77' command and `f77.1' man page in
- the `/usr' or `/usr/local' heirarchy, even if the `f77-install-ok'
- file exists in the source or build directory. See the
- installation documentation for more information.
-
- * `g77' no longer installs the `libf2c.a' library and `f2c.h'
- include file in the `/usr' or `/usr/local' heirarchy, even if the
- `f2c-install-ok' or `f2c-exists-ok' files exist in the source or
- build directory. See the installation documentation for more
- information.
-
- * The `libf2c.a' library produced by `g77' has been renamed to
- `libg2c.a'. It is installed only in the `gcc' "private" directory
- heirarchy, `gcc-lib'. This allows system administrators and users
- to choose which version of the `libf2c' library from `netlib' they
- wish to use on a case-by-case basis. See the installation
- documentation for more information.
-
- * The `f2c.h' include (header) file produced by `g77' has been
- renamed to `g2c.h'. It is installed only in the `gcc' "private"
- directory heirarchy, `gcc-lib'. This allows system administrators
- and users to choose which version of the include file from
- `netlib' they wish to use on a case-by-case basis. See the
- installation documentation for more information.
-
- * The `g77' command now expects the run-time library to be named
- `libg2c.a' instead of `libf2c.a', to ensure that a version other
- than the one built and installed as part of the same `g77' version
- is picked up.
-
- * The `-Wunused' option no longer issues a spurious warning about
- the "master" procedure generated by `g77' for procedures
- containing `ENTRY' statements.
-
- * `g77''s version of `libf2c' separates out the setting of global
- state (such as command-line arguments and signal handling) from
- `main.o' into distinct, new library archive members.
-
- This should make it easier to write portable applications that
- have their own (non-Fortran) `main()' routine properly set up the
- `libf2c' environment, even when `libf2c' (now `libg2c') is a
- shared library.
-
- * During the configuration and build process, `g77' creates
- subdirectories it needs only as it needs them, thus avoiding
- unnecessary creation of, for example, `stage1/f/runtime' when
- doing a non-bootstrap build. Other cleaning up of the
- configuration and build process has been performed as well.
-
- * `install-info' now used to update the directory of Info
- documentation to contain an entry for `g77' (during installation).
-
- * Some diagnostics have been changed from warnings to errors, to
- prevent inadvertent use of the resulting, probably buggy, programs.
- These mostly include diagnostics about use of unsupported features
- in the `OPEN', `INQUIRE', `READ', and `WRITE' statements, and
- about truncations of various sorts of constants.
-
- * Improve documentation and indexing.
-
- * Upgrade to `libf2c' as of 1998-04-20.
-
- This should fix a variety of problems, including those involving
- some uses of the `T' format specifier, and perhaps some build
- (porting) problems as well.
-
-In 0.5.22 (versus 0.5.21):
-==========================
-
- * Fix code generation for iterative `DO' loops that have one or more
- references to the iteration variable, or to aliases of it, in
- their control expressions. For example, `DO 10 J=2,J' now is
- compiled correctly.
-
- * Fix a code-generation bug that afflicted Intel x86 targets when
- `-O2' was specified compiling, for example, an old version of the
- `DNRM2' routine.
-
- The x87 coprocessor stack was being mismanaged in cases involving
- assigned `GOTO' and `ASSIGN'.
-
- * Fix `DTime' intrinsic so as not to truncate results to integer
- values (on some systems).
-
- * Fix `Signal' intrinsic so it offers portable support for 64-bit
- systems (such as Digital Alphas running GNU/Linux).
-
- * Fix run-time crash involving `NAMELIST' on 64-bit machines such as
- Alphas.
-
- * Fix `g77' version of `libf2c' so it no longer produces a spurious
- `I/O recursion' diagnostic at run time when an I/O operation (such
- as `READ *,I') is interrupted in a manner that causes the program
- to be terminated via the `f_exit' routine (such as via `C-c').
-
- * Fix `g77' crash triggered by `CASE' statement with an omitted
- lower or upper bound.
-
- * Fix `g77' crash compiling references to `CPU_Time' intrinsic.
-
- * Fix `g77' crash (or apparently infinite run-time) when compiling
- certain complicated expressions involving `COMPLEX' arithmetic
- (especially multiplication).
-
- * Fix `g77' crash on statements such as `PRINT *,
- (REAL(Z(I)),I=1,2)', where `Z' is `DOUBLE COMPLEX'.
-
- * Fix a `g++' crash.
-
- * Support `FORMAT(I<EXPR>)' when EXPR is a compile-time constant
- `INTEGER' expression.
-
- * Fix `g77' `-g' option so procedures that use `ENTRY' can be
- stepped through, line by line, in `gdb'.
-
- * Fix a profiling-related bug in `gcc' back end for Intel x86
- architecture.
-
- * Allow any `REAL' argument to intrinsics `Second' and `CPU_Time'.
-
- * Allow any numeric argument to intrinsics `Int2' and `Int8'.
-
- * Use `tempnam', if available, to open scratch files (as in
- `OPEN(STATUS='SCRATCH')') so that the `TMPDIR' environment
- variable, if present, is used.
-
- * Rename the `gcc' keyword `restrict' to `__restrict__', to avoid
- rejecting valid, existing, C programs. Support for `restrict' is
- now more like support for `complex'.
-
- * Fix `-fpedantic' to not reject procedure invocations such as
- `I=J()' and `CALL FOO()'.
-
- * Fix `-fugly-comma' to affect invocations of only external
- procedures. Restore rejection of gratuitous trailing omitted
- arguments to intrinsics, as in `I=MAX(3,4,,)'.
-
- * Fix compiler so it accepts `-fgnu-intrinsics-*' and
- `-fbadu77-intrinsics-*' options.
-
- * Improve diagnostic messages from `libf2c' so it is more likely
- that the printing of the active format string is limited to the
- string, with no trailing garbage being printed.
-
- (Unlike `f2c', `g77' did not append a null byte to its compiled
- form of every format string specified via a `FORMAT' statement.
- However, `f2c' would exhibit the problem anyway for a statement
- like `PRINT '(I)garbage', 1' by printing `(I)garbage' as the
- format string.)
-
- * Improve compilation of `FORMAT' expressions so that a null byte is
- appended to the last operand if it is a constant. This provides a
- cleaner run-time diagnostic as provided by `libf2c' for statements
- like `PRINT '(I1', 42'.
-
- * Fix various crashes involving code with diagnosed errors.
-
- * Fix cross-compilation bug when configuring `libf2c'.
-
- * Improve diagnostics.
-
- * Improve documentation and indexing.
-
- * Upgrade to `libf2c' as of 1997-09-23. This fixes a formatted-I/O
- bug that afflicted 64-bit systems with 32-bit integers (such as
- Digital Alpha running GNU/Linux).
-
-In `egcs' 1.0.2 (versus `egcs' 1.0.1):
-======================================
-
- * Fix `g77' crash triggered by `CASE' statement with an omitted
- lower or upper bound.
-
- * Fix `g77' crash on statements such as `PRINT *,
- (REAL(Z(I)),I=1,2)', where `Z' is `DOUBLE COMPLEX'.
-
- * Fix `-fPIC' (such as compiling for ELF targets) on the Intel x86
- architecture target so invalid assembler code is no longer
- produced.
-
- * Fix `-fpedantic' to not reject procedure invocations such as
- `I=J()' and `CALL FOO()'.
-
- * Fix `-fugly-comma' to affect invocations of only external
- procedures. Restore rejection of gratuitous trailing omitted
- arguments to intrinsics, as in `I=MAX(3,4,,)'.
-
- * Fix compiler so it accepts `-fgnu-intrinsics-*' and
- `-fbadu77-intrinsics-*' options.
-
-In `egcs' 1.0.1 (versus `egcs' 1.0):
-====================================
-
- * Fix run-time crash involving `NAMELIST' on 64-bit machines such as
- Alphas.
-
-In `egcs' 1.0 (versus 0.5.21):
-==============================
-
- * Version 1.0 of `egcs' contains several regressions against version
- 0.5.21 of `g77', due to using the "vanilla" `gcc' back end instead
- of patching it to fix a few bugs and improve performance in a few
- cases.
-
- *Note Actual Bugs We Haven't Fixed Yet: Actual Bugs, available in
- plain-text format in `gcc/f/BUGS', for information on the known
- bugs in this version, including the regressions.
-
- Features that have been dropped from this version of `g77' due to
- their being implemented via `g77'-specific patches to the `gcc'
- back end in previous releases include:
-
- - Support for the C-language `restrict' keyword.
-
- - Support for the `-W' option warning about integer division by
- zero.
-
- - The Intel x86-specific option `-malign-double' applying to
- stack-allocated data as well as statically-allocate data.
-
- Note that the `gcc/f/gbe/' subdirectory has been removed from this
- distribution as a result of `g77' being fully integrated with the
- `egcs' variant of the `gcc' back end.
-
- * Fix code generation for iterative `DO' loops that have one or more
- references to the iteration variable, or to aliases of it, in
- their control expressions. For example, `DO 10 J=2,J' now is
- compiled correctly.
-
- * Fix `DTime' intrinsic so as not to truncate results to integer
- values (on some systems).
-
- * Some Fortran code, miscompiled by `g77' built on `gcc' version
- 2.8.1 on m68k-next-nextstep3 configurations when using the `-O2'
- option, is now compiled correctly. It is believed that a C
- function known to miscompile on that configuration when using the
- `-O2 -funroll-loops' options also is now compiled correctly.
-
- * Remove support for non-`egcs' versions of `gcc'.
-
- * Remove support for the `--driver' option, as `g77' now does all
- the driving, just like `gcc'.
-
- * Allow any numeric argument to intrinsics `Int2' and `Int8'.
-
- * Improve diagnostic messages from `libf2c' so it is more likely
- that the printing of the active format string is limited to the
- string, with no trailing garbage being printed.
-
- (Unlike `f2c', `g77' did not append a null byte to its compiled
- form of every format string specified via a `FORMAT' statement.
- However, `f2c' would exhibit the problem anyway for a statement
- like `PRINT '(I)garbage', 1' by printing `(I)garbage' as the
- format string.)
-
- * Upgrade to `libf2c' as of 1997-09-23. This fixes a formatted-I/O
- bug that afflicted 64-bit systems with 32-bit integers (such as
- Digital Alpha running GNU/Linux).
-
-In 0.5.21:
-==========
-
- * Fix a code-generation bug introduced by 0.5.20 caused by loop
- unrolling (by specifying `-funroll-loops' or similar). This bug
- afflicted all code compiled by version 2.7.2.2.f.2 of `gcc' (C,
- C++, Fortran, and so on).
-
- * Fix a code-generation bug manifested when combining local
- `EQUIVALENCE' with a `DATA' statement that follows the first
- executable statement (or is treated as an executable-context
- statement as a result of using the `-fpedantic' option).
-
- * Fix a compiler crash that occured when an integer division by a
- constant zero is detected. Instead, when the `-W' option is
- specified, the `gcc' back end issues a warning about such a case.
- This bug afflicted all code compiled by version 2.7.2.2.f.2 of
- `gcc' (C, C++, Fortran, and so on).
-
- * Fix a compiler crash that occurred in some cases of procedure
- inlining. (Such cases became more frequent in 0.5.20.)
-
- * Fix a compiler crash resulting from using `DATA' or similar to
- initialize a `COMPLEX' variable or array to zero.
-
- * Fix compiler crashes involving use of `AND', `OR', or `XOR'
- intrinsics.
-
- * Fix compiler bug triggered when using a `COMMON' or `EQUIVALENCE'
- variable as the target of an `ASSIGN' or assigned-`GOTO' statement.
-
- * Fix compiler crashes due to using the name of a some non-standard
- intrinsics (such as `FTELL' or `FPUTC') as such and as the name of
- a procedure or common block. Such dual use of a name in a program
- is allowed by the standard.
-
- * Place automatic arrays on the stack, even if `SAVE' or the
- `-fno-automatic' option is in effect. This avoids a compiler
- crash in some cases.
-
- * The `-malign-double' option now reliably aligns `DOUBLE PRECISION'
- optimally on Pentium and Pentium Pro architectures (586 and 686 in
- `gcc').
-
- * New option `-Wno-globals' disables warnings about "suspicious" use
- of a name both as a global name and as the implicit name of an
- intrinsic, and warnings about disagreements over the number or
- natures of arguments passed to global procedures, or the natures
- of the procedures themselves.
-
- The default is to issue such warnings, which are new as of this
- version of `g77'.
-
- * New option `-fno-globals' disables diagnostics about potentially
- fatal disagreements analysis problems, such as disagreements over
- the number or natures of arguments passed to global procedures, or
- the natures of those procedures themselves.
-
- The default is to issue such diagnostics and flag the compilation
- as unsuccessful. With this option, the diagnostics are issued as
- warnings, or, if `-Wno-globals' is specified, are not issued at
- all.
-
- This option also disables inlining of global procedures, to avoid
- compiler crashes resulting from coding errors that these
- diagnostics normally would identify.
-
- * Diagnose cases where a reference to a procedure disagrees with the
- type of that procedure, or where disagreements about the number or
- nature of arguments exist. This avoids a compiler crash.
-
- * Fix parsing bug whereby `g77' rejected a second initialization
- specification immediately following the first's closing `/' without
- an intervening comma in a `DATA' statement, and the second
- specification was an implied-DO list.
-
- * Improve performance of the `gcc' back end so certain complicated
- expressions involving `COMPLEX' arithmetic (especially
- multiplication) don't appear to take forever to compile.
-
- * Fix a couple of profiling-related bugs in `gcc' back end.
-
- * Integrate GNU Ada's (GNAT's) changes to the back end, which
- consist almost entirely of bug fixes. These fixes are circa
- version 3.10p of GNAT.
-
- * Include some other `gcc' fixes that seem useful in `g77''s version
- of `gcc'. (See `gcc/ChangeLog' for details--compare it to that
- file in the vanilla `gcc-2.7.2.3.tar.gz' distribution.)
-
- * Fix `libU77' routines that accept file and other names to strip
- trailing blanks from them, for consistency with other
- implementations. Blanks may be forcibly appended to such names by
- appending a single null character (`CHAR(0)') to the significant
- trailing blanks.
-
- * Fix `CHMOD' intrinsic to work with file names that have embedded
- blanks, commas, and so on.
-
- * Fix `SIGNAL' intrinsic so it accepts an optional third `Status'
- argument.
-
- * Fix `IDATE()' intrinsic subroutine (VXT form) so it accepts
- arguments in the correct order. Documentation fixed accordingly,
- and for `GMTIME()' and `LTIME()' as well.
-
- * Make many changes to `libU77' intrinsics to support existing code
- more directly.
-
- Such changes include allowing both subroutine and function forms
- of many routines, changing `MCLOCK()' and `TIME()' to return
- `INTEGER(KIND=1)' values, introducing `MCLOCK8()' and `TIME8()' to
- return `INTEGER(KIND=2)' values, and placing functions that are
- intended to perform side effects in a new intrinsic group,
- `badu77'.
-
- * Improve `libU77' so it is more portable.
-
- * Add options `-fbadu77-intrinsics-delete',
- `-fbadu77-intrinsics-hide', and so on.
-
- * Fix crashes involving diagnosed or invalid code.
-
- * `g77' and `gcc' now do a somewhat better job detecting and
- diagnosing arrays that are too large to handle before these cause
- diagnostics during the assembler or linker phase, a compiler
- crash, or generation of incorrect code.
-
- * Make some fixes to alias analysis code.
-
- * Add support for `restrict' keyword in `gcc' front end.
-
- * Support `gcc' version 2.7.2.3 (modified by `g77' into version
- 2.7.2.3.f.1), and remove support for prior versions of `gcc'.
-
- * Incorporate GNAT's patches to the `gcc' back end into `g77''s, so
- GNAT users do not need to apply GNAT's patches to build both GNAT
- and `g77' from the same source tree.
-
- * Modify `make' rules and related code so that generation of Info
- documentation doesn't require compilation using `gcc'. Now, any
- ANSI C compiler should be adequate to produce the `g77'
- documentation (in particular, the tables of intrinsics) from
- scratch.
-
- * Add `INT2' and `INT8' intrinsics.
-
- * Add `CPU_TIME' intrinsic.
-
- * Add `ALARM' intrinsic.
-
- * `CTIME' intrinsic now accepts any `INTEGER' argument, not just
- `INTEGER(KIND=2)'.
-
- * Warn when explicit type declaration disagrees with the type of an
- intrinsic invocation.
-
- * Support `*f771' entry in `gcc' `specs' file.
-
- * Fix typo in `make' rule `g77-cross', used only for cross-compiling.
-
- * Fix `libf2c' build procedure to re-archive library if previous
- attempt to archive was interrupted.
-
- * Change `gcc' to unroll loops only during the last invocation (of
- as many as two invocations) of loop optimization.
-
- * Improve handling of `-fno-f2c' so that code that attempts to pass
- an intrinsic as an actual argument, such as `CALL FOO(ABS)', is
- rejected due to the fact that the run-time-library routine is,
- effectively, compiled with `-ff2c' in effect.
-
- * Fix `g77' driver to recognize `-fsyntax-only' as an option that
- inhibits linking, just like `-c' or `-S', and to recognize and
- properly handle the `-nostdlib', `-M', `-MM', `-nodefaultlibs',
- and `-Xlinker' options.
-
- * Upgrade to `libf2c' as of 1997-08-16.
-
- * Modify `libf2c' to consistently and clearly diagnose recursive I/O
- (at run time).
-
- * `g77' driver now prints version information (such as produced by
- `g77 -v') to `stderr' instead of `stdout'.
-
- * The `.r' suffix now designates a Ratfor source file, to be
- preprocessed via the `ratfor' command, available separately.
-
- * Fix some aspects of how `gcc' determines what kind of system is
- being configured and what kinds are supported. For example, GNU
- Linux/Alpha ELF systems now are directly supported.
-
- * Improve diagnostics.
-
- * Improve documentation and indexing.
-
- * Include all pertinent files for `libf2c' that come from
- `netlib.bell-labs.com'; give any such files that aren't quite
- accurate in `g77''s version of `libf2c' the suffix `.netlib'.
-
- * Reserve `INTEGER(KIND=0)' for future use.
-
-In 0.5.20:
-==========
-
- * The `-fno-typeless-boz' option is now the default.
-
- This option specifies that non-decimal-radix constants using the
- prefixed-radix form (such as `Z'1234'') are to be interpreted as
- `INTEGER' constants. Specify `-ftypeless-boz' to cause such
- constants to be interpreted as typeless.
-
- (Version 0.5.19 introduced `-fno-typeless-boz' and its inverse.)
-
- * Options `-ff90-intrinsics-enable' and `-fvxt-intrinsics-enable'
- now are the defaults.
-
- Some programs might use names that clash with intrinsic names
- defined (and now enabled) by these options or by the new `libU77'
- intrinsics. Users of such programs might need to compile them
- differently (using, for example, `-ff90-intrinsics-disable') or,
- better yet, insert appropriate `EXTERNAL' statements specifying
- that these names are not intended to be names of intrinsics.
-
- * The `ALWAYS_FLUSH' macro is no longer defined when building
- `libf2c', which should result in improved I/O performance,
- especially over NFS.
-
- *Note:* If you have code that depends on the behavior of `libf2c'
- when built with `ALWAYS_FLUSH' defined, you will have to modify
- `libf2c' accordingly before building it from this and future
- versions of `g77'.
-
- * Dave Love's implementation of `libU77' has been added to the
- version of `libf2c' distributed with and built as part of `g77'.
- `g77' now knows about the routines in this library as intrinsics.
-
- * New option `-fvxt' specifies that the source file is written in
- VXT Fortran, instead of GNU Fortran.
-
- * The `-fvxt-not-f90' option has been deleted, along with its
- inverse, `-ff90-not-vxt'.
-
- If you used one of these deleted options, you should re-read the
- pertinent documentation to determine which options, if any, are
- appropriate for compiling your code with this version of `g77'.
-
- * The `-fugly' option now issues a warning, as it likely will be
- removed in a future version.
-
- (Enabling all the `-fugly-*' options is unlikely to be feasible,
- or sensible, in the future, so users should learn to specify only
- those `-fugly-*' options they really need for a particular source
- file.)
-
- * The `-fugly-assumed' option, introduced in version 0.5.19, has
- been changed to better accommodate old and new code.
-
- * Make a number of fixes to the `g77' front end and the `gcc' back
- end to better support Alpha (AXP) machines. This includes
- providing at least one bug-fix to the `gcc' back end for Alphas.
-
- * Related to supporting Alpha (AXP) machines, the `LOC()' intrinsic
- and `%LOC()' construct now return values of integer type that is
- the same width (holds the same number of bits) as the pointer type
- on the machine.
-
- On most machines, this won't make a difference, whereas on Alphas,
- the type these constructs return is `INTEGER*8' instead of the
- more common `INTEGER*4'.
-
- * Emulate `COMPLEX' arithmetic in the `g77' front end, to avoid bugs
- in `complex' support in the `gcc' back end. New option
- `-fno-emulate-complex' causes `g77' to revert the 0.5.19 behavior.
-
- * Fix bug whereby `REAL A(1)', for example, caused a compiler crash
- if `-fugly-assumed' was in effect and A was a local (automatic)
- array. That case is no longer affected by the new handling of
- `-fugly-assumed'.
-
- * Fix `g77' command driver so that `g77 -o foo.f' no longer deletes
- `foo.f' before issuing other diagnostics, and so the `-x' option
- is properly handled.
-
- * Enable inlining of subroutines and functions by the `gcc' back end.
- This works as it does for `gcc' itself--program units may be
- inlined for invocations that follow them in the same program unit,
- as long as the appropriate compile-time options are specified.
-
- * Dummy arguments are no longer assumed to potentially alias
- (overlap) other dummy arguments or `COMMON' areas when any of
- these are defined (assigned to) by Fortran code.
-
- This can result in faster and/or smaller programs when compiling
- with optimization enabled, though on some systems this effect is
- observed only when `-fforce-addr' also is specified.
-
- New options `-falias-check', `-fargument-alias',
- `-fargument-noalias', and `-fno-argument-noalias-global' control
- the way `g77' handles potential aliasing.
-
- * The `CONJG()' and `DCONJG()' intrinsics now are compiled in-line.
-
- * The bug-fix for 0.5.19.1 has been re-done. The `g77' compiler has
- been changed back to assume `libf2c' has no aliasing problems in
- its implementations of the `COMPLEX' (and `DOUBLE COMPLEX')
- intrinsics. The `libf2c' has been changed to have no such
- problems.
-
- As a result, 0.5.20 is expected to offer improved performance over
- 0.5.19.1, perhaps as good as 0.5.19 in most or all cases, due to
- this change alone.
-
- *Note:* This change requires version 0.5.20 of `libf2c', at least,
- when linking code produced by any versions of `g77' other than
- 0.5.19.1. Use `g77 -v' to determine the version numbers of the
- `libF77', `libI77', and `libU77' components of the `libf2c'
- library. (If these version numbers are not printed--in
- particular, if the linker complains about unresolved references to
- names like `g77__fvers__'--that strongly suggests your
- installation has an obsolete version of `libf2c'.)
-
- * New option `-fugly-assign' specifies that the same memory
- locations are to be used to hold the values assigned by both
- statements `I = 3' and `ASSIGN 10 TO I', for example. (Normally,
- `g77' uses a separate memory location to hold assigned statement
- labels.)
-
- * `FORMAT' and `ENTRY' statements now are allowed to precede
- `IMPLICIT NONE' statements.
-
- * Produce diagnostic for unsupported `SELECT CASE' on `CHARACTER'
- type, instead of crashing, at compile time.
-
- * Fix crashes involving diagnosed or invalid code.
-
- * Change approach to building `libf2c' archive (`libf2c.a') so that
- members are added to it only when truly necessary, so the user
- that installs an already-built `g77' doesn't need to have write
- access to the build tree (whereas the user doing the build might
- not have access to install new software on the system).
-
- * Support `gcc' version 2.7.2.2 (modified by `g77' into version
- 2.7.2.2.f.2), and remove support for prior versions of `gcc'.
-
- * Upgrade to `libf2c' as of 1997-02-08, and fix up some of the build
- procedures.
-
- * Improve general build procedures for `g77', fixing minor bugs
- (such as deletion of any file named `f771' in the parent directory
- of `gcc/').
-
- * Enable full support of `INTEGER*8' available in `libf2c' and
- `f2c.h' so that `f2c' users may make full use of its features via
- the `g77' version of `f2c.h' and the `INTEGER*8' support routines
- in the `g77' version of `libf2c'.
-
- * Improve `g77' driver and `libf2c' so that `g77 -v' yields version
- information on the library.
-
- * The `SNGL' and `FLOAT' intrinsics now are specific intrinsics,
- instead of synonyms for the generic intrinsic `REAL'.
-
- * New intrinsics have been added. These are `REALPART', `IMAGPART',
- `COMPLEX', `LONG', and `SHORT'.
-
- * A new group of intrinsics, `gnu', has been added to contain the
- new `REALPART', `IMAGPART', and `COMPLEX' intrinsics. An old
- group, `dcp', has been removed.
-
- * Complain about industry-wide ambiguous references `REAL(EXPR)' and
- `AIMAG(EXPR)', where EXPR is `DOUBLE COMPLEX' (or any complex type
- other than `COMPLEX'), unless `-ff90' option specifies Fortran 90
- interpretation or new `-fugly-complex' option, in conjunction with
- `-fnot-f90', specifies `f2c' interpretation.
-
- * Make improvements to diagnostics.
-
- * Speed up compiler a bit.
-
- * Improvements to documentation and indexing, including a new
- chapter containing information on one, later more, diagnostics
- that users are directed to pull up automatically via a message in
- the diagnostic itself.
-
- (Hence the menu item `M' for the node `Diagnostics' in the
- top-level menu of the Info documentation.)
-
-In 0.5.19.1:
-============
-
- * Code-generation bugs afflicting operations on complex data have
- been fixed.
-
- These bugs occurred when assigning the result of an operation to a
- complex variable (or array element) that also served as an input
- to that operation.
-
- The operations affected by this bug were: `CONJG()', `DCONJG()',
- `CCOS()', `CDCOS()', `CLOG()', `CDLOG()', `CSIN()', `CDSIN()',
- `CSQRT()', `CDSQRT()', complex division, and raising a `DOUBLE
- COMPLEX' operand to an `INTEGER' power. (The related generic and
- `Z'-prefixed intrinsics, such as `ZSIN()', also were affected.)
-
- For example, `C = CSQRT(C)', `Z = Z/C', and `Z = Z**I' (where `C'
- is `COMPLEX' and `Z' is `DOUBLE COMPLEX') have been fixed.
-
-In 0.5.19:
-==========
-
- * Fix `FORMAT' statement parsing so negative values for specifiers
- such as `P' (e.g. `FORMAT(-1PF8.1)') are correctly processed as
- negative.
-
- * Fix `SIGNAL' intrinsic so it once again accepts a procedure as its
- second argument.
-
- * A temporary kludge option provides bare-bones information on
- `COMMON' and `EQUIVALENCE' members at debug time.
-
- * New `-fonetrip' option specifies FORTRAN-66-style one-trip `DO'
- loops.
-
- * New `-fno-silent' option causes names of program units to be
- printed as they are compiled, in a fashion similar to UNIX `f77'
- and `f2c'.
-
- * New `-fugly-assumed' option specifies that arrays dimensioned via
- `DIMENSION X(1)', for example, are to be treated as assumed-size.
-
- * New `-fno-typeless-boz' option specifies that non-decimal-radix
- constants using the prefixed-radix form (such as `Z'1234'') are to
- be interpreted as `INTEGER' constants.
-
- * New `-ff66' option is a "shorthand" option that specifies
- behaviors considered appropriate for FORTRAN 66 programs.
-
- * New `-ff77' option is a "shorthand" option that specifies
- behaviors considered appropriate for UNIX `f77' programs.
-
- * New `-fugly-comma' and `-fugly-logint' options provided to perform
- some of what `-fugly' used to do. `-fugly' and `-fno-ugly' are
- now "shorthand" options, in that they do nothing more than enable
- (or disable) other `-fugly-*' options.
-
- * Fix parsing of assignment statements involving targets that are
- substrings of elements of `CHARACTER' arrays having names such as
- `READ', `WRITE', `GOTO', and `REALFUNCTIONFOO'.
-
- * Fix crashes involving diagnosed code.
-
- * Fix handling of local `EQUIVALENCE' areas so certain cases of
- valid Fortran programs are not misdiagnosed as improperly
- extending the area backwards.
-
- * Support `gcc' version 2.7.2.1.
-
- * Upgrade to `libf2c' as of 1996-09-26, and fix up some of the build
- procedures.
-
- * Change code generation for list-directed I/O so it allows for new
- versions of `libf2c' that might return non-zero status codes for
- some operations previously assumed to always return zero.
-
- This change not only affects how `IOSTAT=' variables are set by
- list-directed I/O, it also affects whether `END=' and `ERR='
- labels are reached by these operations.
-
- * Add intrinsic support for new `FTELL' and `FSEEK' procedures in
- `libf2c'.
-
- * Modify `fseek_()' in `libf2c' to be more portable (though, in
- practice, there might be no systems where this matters) and to
- catch invalid `whence' arguments.
-
- * Some useless warnings from the `-Wunused' option have been
- eliminated.
-
- * Fix a problem building the `f771' executable on AIX systems by
- linking with the `-bbigtoc' option.
-
- * Abort configuration if `gcc' has not been patched using the patch
- file provided in the `gcc/f/gbe/' subdirectory.
-
- * Add options `--help' and `--version' to the `g77' command, to
- conform to GNU coding guidelines. Also add printing of `g77'
- version number when the `--verbose' (`-v') option is used.
-
- * Change internally generated name for local `EQUIVALENCE' areas to
- one based on the alphabetically sorted first name in the list of
- names for entities placed at the beginning of the areas.
-
- * Improvements to documentation and indexing.
-
-In 0.5.18:
-==========
-
- * Add some rudimentary support for `INTEGER*1', `INTEGER*2',
- `INTEGER*8', and their `LOGICAL' equivalents. (This support works
- on most, maybe all, `gcc' targets.)
-
- Thanks to Scott Snyder (<snyder@d0sgif.fnal.gov>) for providing
- the patch for this!
-
- Among the missing elements from the support for these features are
- full intrinsic support and constants.
-
- * Add some rudimentary support for the `BYTE' and `WORD'
- type-declaration statements. `BYTE' corresponds to `INTEGER*1',
- while `WORD' corresponds to `INTEGER*2'.
-
- Thanks to Scott Snyder (<snyder@d0sgif.fnal.gov>) for providing
- the patch for this!
-
- * The compiler code handling intrinsics has been largely rewritten
- to accommodate the new types. No new intrinsics or arguments for
- existing intrinsics have been added, so there is, at this point,
- no intrinsic to convert to `INTEGER*8', for example.
-
- * Support automatic arrays in procedures.
-
- * Reduce space/time requirements for handling large *sparsely*
- initialized aggregate arrays. This improvement applies to only a
- subset of the general problem to be addressed in 0.6.
-
- * Treat initial values of zero as if they weren't specified (in DATA
- and type-declaration statements). The initial values will be set
- to zero anyway, but the amount of compile time processing them
- will be reduced, in some cases significantly (though, again, this
- is only a subset of the general problem to be addressed in 0.6).
-
- A new option, `-fzeros', is introduced to enable the traditional
- treatment of zeros as any other value.
-
- * With `-ff90' in force, `g77' incorrectly interpreted `REAL(Z)' as
- returning a `REAL' result, instead of as a `DOUBLE PRECISION'
- result. (Here, `Z' is `DOUBLE COMPLEX'.)
-
- With `-fno-f90' in force, the interpretation remains unchanged,
- since this appears to be how at least some F77 code using the
- `DOUBLE COMPLEX' extension expected it to work.
-
- Essentially, `REAL(Z)' in F90 is the same as `DBLE(Z)', while in
- extended F77, it appears to be the same as `REAL(REAL(Z))'.
-
- * An expression involving exponentiation, where both operands were
- type `INTEGER' and the right-hand operand was negative, was
- erroneously evaluated.
-
- * Fix bugs involving `DATA' implied-`DO' constructs (these involved
- an errant diagnostic and a crash, both on good code, one involving
- subsequent statement-function definition).
-
- * Close `INCLUDE' files after processing them, so compiling source
- files with lots of `INCLUDE' statements does not result in being
- unable to open `INCLUDE' files after all the available file
- descriptors are used up.
-
- * Speed up compiling, especially of larger programs, and perhaps
- slightly reduce memory utilization while compiling (this is *not*
- the improvement planned for 0.6 involving large aggregate
- areas)--these improvements result from simply turning off some
- low-level code to do self-checking that hasn't been triggered in a
- long time.
-
- * Introduce three new options that implement optimizations in the
- `gcc' back end (GBE). These options are `-fmove-all-movables',
- `-freduce-all-givs', and `-frerun-loop-opt', which are enabled, by
- default, for Fortran compilations. These optimizations are
- intended to help toon Fortran programs.
-
- * Patch the GBE to do a better job optimizing certain kinds of
- references to array elements.
-
- * Due to patches to the GBE, the version number of `gcc' also is
- patched to make it easier to manage installations, especially
- useful if it turns out a `g77' change to the GBE has a bug.
-
- The `g77'-modified version number is the `gcc' version number with
- the string `.f.N' appended, where `f' identifies the version as
- enhanced for Fortran, and N is `1' for the first Fortran patch for
- that version of `gcc', `2' for the second, and so on.
-
- So, this introduces version 2.7.2.f.1 of `gcc'.
-
- * Make several improvements and fixes to diagnostics, including the
- removal of two that were inappropriate or inadequate.
-
- * Warning about two successive arithmetic operators, produced by
- `-Wsurprising', now produced *only* when both operators are,
- indeed, arithmetic (not relational/boolean).
-
- * `-Wsurprising' now warns about the remaining cases of using
- non-integral variables for implied-`DO' loops, instead of these
- being rejected unless `-fpedantic' or `-fugly' specified.
-
- * Allow `SAVE' of a local variable or array, even after it has been
- given an initial value via `DATA', for example.
-
- * Introduce an Info version of `g77' documentation, which supercedes
- `gcc/f/CREDITS', `gcc/f/DOC', and `gcc/f/PROJECTS'. These files
- will be removed in a future release. The files `gcc/f/BUGS',
- `gcc/f/INSTALL', and `gcc/f/NEWS' now are automatically built from
- the texinfo source when distributions are made.
-
- This effort was inspired by a first pass at translating
- `g77-0.5.16/f/DOC' that was contributed to Craig by David Ronis
- (<ronis@onsager.chem.mcgill.ca>).
-
- * New `-fno-second-underscore' option to specify that, when
- `-funderscoring' is in effect, a second underscore is not to be
- appended to Fortran names already containing an underscore.
-
- * Change the way iterative `DO' loops work to follow the F90
- standard. In particular, calculation of the iteration count is
- still done by converting the start, end, and increment parameters
- to the type of the `DO' variable, but the result of the
- calculation is always converted to the default `INTEGER' type.
-
- (This should have no effect on existing code compiled by `g77',
- but code written to assume that use of a *wider* type for the `DO'
- variable will result in an iteration count being fully calculated
- using that wider type (wider than default `INTEGER') must be
- rewritten.)
-
- * Support `gcc' version 2.7.2.
-
- * Upgrade to `libf2c' as of 1996-03-23, and fix up some of the build
- procedures.
-
- Note that the email addresses related to `f2c' have changed--the
- distribution site now is named `netlib.bell-labs.com', and the
- maintainer's new address is <dmg@bell-labs.com>.
-
-In 0.5.17:
-==========
-
- * *Fix serious bug* in `g77 -v' command that can cause removal of a
- system's `/dev/null' special file if run by user `root'.
-
- *All users* of version 0.5.16 should ensure that they have not
- removed `/dev/null' or replaced it with an ordinary file (e.g. by
- comparing the output of `ls -l /dev/null' with `ls -l /dev/zero'.
- If the output isn't basically the same, contact your system
- administrator about restoring `/dev/null' to its proper status).
-
- This bug is particularly insidious because removing `/dev/null' as
- a special file can go undetected for quite a while, aside from
- various applications and programs exhibiting sudden, strange
- behaviors.
-
- I sincerely apologize for not realizing the implications of the
- fact that when `g77 -v' runs the `ld' command with `-o /dev/null'
- that `ld' tries to *remove* the executable it is supposed to build
- (especially if it reports unresolved references, which it should
- in this case)!
-
- * Fix crash on `CHARACTER*(*) FOO' in a main or block data program
- unit.
-
- * Fix crash that can occur when diagnostics given outside of any
- program unit (such as when input file contains `@foo').
-
- * Fix crashes, infinite loops (hangs), and such involving diagnosed
- code.
-
- * Fix `ASSIGN''ed variables so they can be `SAVE''d or dummy
- arguments, and issue clearer error message in cases where target
- of `ASSIGN' or `ASSIGN'ed `GOTO'/`FORMAT' is too small (which
- should never happen).
-
- * Make `libf2c' build procedures work on more systems again by
- eliminating unnecessary invocations of `ld -r -x' and `mv'.
-
- * Fix omission of `-funix-intrinsics-...' options in list of
- permitted options to compiler.
-
- * Fix failure to always diagnose missing type declaration for
- `IMPLICIT NONE'.
-
- * Fix compile-time performance problem (which could sometimes crash
- the compiler, cause a hang, or whatever, due to a bug in the back
- end) involving exponentiation with a large `INTEGER' constant for
- the right-hand operator (e.g. `I**32767').
-
- * Fix build procedures so cross-compiling `g77' (the `fini' utility
- in particular) is properly built using the host compiler.
-
- * Add new `-Wsurprising' option to warn about constructs that are
- interpreted by the Fortran standard (and `g77') in ways that are
- surprising to many programmers.
-
- * Add `ERF()' and `ERFC()' as generic intrinsics mapping to existing
- `ERF'/`DERF' and `ERFC'/`DERFC' specific intrinsics.
-
- *Note:* You should specify `INTRINSIC ERF,ERFC' in any code where
- you might use these as generic intrinsics, to improve likelihood
- of diagnostics (instead of subtle run-time bugs) when using a
- compiler that doesn't support these as intrinsics (e.g. `f2c').
-
- * Remove from `-fno-pedantic' the diagnostic about `DO' with
- non-`INTEGER' index variable; issue that under `-Wsurprising'
- instead.
-
- * Clarify some diagnostics that say things like "ignored" when that's
- misleading.
-
- * Clarify diagnostic on use of `.EQ.'/`.NE.' on `LOGICAL' operands.
-
- * Minor improvements to code generation for various operations on
- `LOGICAL' operands.
-
- * Minor improvement to code generation for some `DO' loops on some
- machines.
-
- * Support `gcc' version 2.7.1.
-
- * Upgrade to `libf2c' as of 1995-11-15.
-
-In 0.5.16:
-==========
-
- * Fix a code-generation bug involving complicated `EQUIVALENCE'
- statements not involving `COMMON'.
-
- * Fix code-generation bugs involving invoking "gratis" library
- procedures in `libf2c' from code compiled with `-fno-f2c' by
- making these procedures known to `g77' as intrinsics (not affected
- by -fno-f2c). This is known to fix code invoking `ERF()',
- `ERFC()', `DERF()', and `DERFC()'.
-
- * Update `libf2c' to include netlib patches through 1995-08-16, and
- `#define' `WANT_LEAD_0' to 1 to make `g77'-compiled code more
- consistent with other Fortran implementations by outputting
- leading zeros in formatted and list-directed output.
-
- * Fix a code-generation bug involving adjustable dummy arrays with
- high bounds whose primaries are changed during procedure
- execution, and which might well improve code-generation
- performance for such arrays compared to `f2c' plus `gcc' (but
- apparently only when using `gcc-2.7.0' or later).
-
- * Fix a code-generation bug involving invocation of `COMPLEX' and
- `DOUBLE COMPLEX' `FUNCTION's and doing `COMPLEX' and `DOUBLE
- COMPLEX' divides, when the result of the invocation or divide is
- assigned directly to a variable that overlaps one or more of the
- arguments to the invocation or divide.
-
- * Fix crash by not generating new optimal code for `X**I' if `I' is
- nonconstant and the expression is used to dimension a dummy array,
- since the `gcc' back end does not support the necessary mechanics
- (and the `gcc' front end rejects the equivalent construct, as it
- turns out).
-
- * Fix crash on expressions like `COMPLEX**INTEGER'.
-
- * Fix crash on expressions like `(1D0,2D0)**2', i.e. raising a
- `DOUBLE COMPLEX' constant to an `INTEGER' constant power.
-
- * Fix crashes and such involving diagnosed code.
-
- * Diagnose, instead of crashing on, statement function definitions
- having duplicate dummy argument names.
-
- * Fix bug causing rejection of good code involving statement function
- definitions.
-
- * Fix bug resulting in debugger not knowing size of local equivalence
- area when any member of area has initial value (via `DATA', for
- example).
-
- * Fix installation bug that prevented installation of `g77' driver.
- Provide for easy selection of whether to install copy of `g77' as
- `f77' to replace the broken code.
-
- * Fix `gcc' driver (affects `g77' thereby) to not gratuitously
- invoke the `f771' program (e.g. when `-E' is specified).
-
- * Fix diagnostic to point to correct source line when it immediately
- follows an `INCLUDE' statement.
-
- * Support more compiler options in `gcc'/`g77' when compiling
- Fortran files. These options include `-p', `-pg', `-aux-info',
- `-P', correct setting of version-number macros for preprocessing,
- full recognition of `-O0', and automatic insertion of
- configuration-specific linker specs.
-
- * Add new intrinsics that interface to existing routines in `libf2c':
- `ABORT', `DERF', `DERFC', `ERF', `ERFC', `EXIT', `FLUSH',
- `GETARG', `GETENV', `IARGC', `SIGNAL', and `SYSTEM'. Note that
- `ABORT', `EXIT', `FLUSH', `SIGNAL', and `SYSTEM' are intrinsic
- subroutines, not functions (since they have side effects), so to
- get the return values from `SIGNAL' and `SYSTEM', append a final
- argument specifying an `INTEGER' variable or array element (e.g.
- `CALL SYSTEM('rm foo',ISTAT)').
-
- * Add new intrinsic group named `unix' to contain the new intrinsics,
- and by default enable this new group.
-
- * Move `LOC()' intrinsic out of the `vxt' group to the new `unix'
- group.
-
- * Improve `g77' so that `g77 -v' by itself (or with certain other
- options, including `-B', `-b', `-i', `-nostdlib', and `-V')
- reports lots more useful version info, and so that long-form
- options `gcc' accepts are understood by `g77' as well (even in
- truncated, unambiguous forms).
-
- * Add new `g77' option `--driver=name' to specify driver when
- default, `gcc', isn't appropriate.
-
- * Add support for `#' directives (as output by the preprocessor) in
- the compiler, and enable generation of those directives by the
- preprocessor (when compiling `.F' files) so diagnostics and
- debugging info are more useful to users of the preprocessor.
-
- * Produce better diagnostics, more like `gcc', with info such as `In
- function `foo':' and `In file included from...:'.
-
- * Support `gcc''s `-fident' and `-fno-ident' options.
-
- * When `-Wunused' in effect, don't warn about local variables used as
- statement-function dummy arguments or `DATA' implied-`DO' iteration
- variables, even though, strictly speaking, these are not uses of
- the variables themselves.
-
- * When `-W -Wunused' in effect, don't warn about unused dummy
- arguments at all, since there's no way to turn this off for
- individual cases (`g77' might someday start warning about
- these)--applies to `gcc' versions 2.7.0 and later, since earlier
- versions didn't warn about unused dummy arguments.
-
- * New option `-fno-underscoring' that inhibits transformation of
- names (by appending one or two underscores) so users may experiment
- with implications of such an environment.
-
- * Minor improvement to `gcc/f/info' module to make it easier to build
- `g77' using the native (non-`gcc') compiler on certain machines
- (but definitely not all machines nor all non-`gcc' compilers).
- Please do not report bugs showing problems compilers have with
- macros defined in `gcc/f/target.h' and used in places like
- `gcc/f/expr.c'.
-
- * Add warning to be printed for each invocation of the compiler if
- the target machine `INTEGER', `REAL', or `LOGICAL' size is not 32
- bits, since `g77' is known to not work well for such cases (to be
- fixed in Version 0.6--*note Actual Bugs We Haven't Fixed Yet:
- Actual Bugs.).
-
- * Lots of new documentation (though work is still needed to put it
- into canonical GNU format).
-
- * Build `libf2c' with `-g0', not `-g2', in effect (by default), to
- produce smaller library without lots of debugging clutter.
-
-In 0.5.15:
-==========
-
- * Fix bad code generation involving `X**I' and temporary, internal
- variables generated by `g77' and the back end (such as for `DO'
- loops).
-
- * Fix crash given `CHARACTER A;DATA A/.TRUE./'.
-
- * Replace crash with diagnostic given `CHARACTER A;DATA A/1.0/'.
-
- * Fix crash or other erratic behavior when null character constant
- (`''') is encountered.
-
- * Fix crash or other erratic behavior involving diagnosed code.
-
- * Fix code generation for external functions returning type `REAL'
- when the `-ff2c' option is in force (which it is by default) so
- that `f2c' compatibility is indeed provided.
-
- * Disallow `COMMON I(10)' if `I' has previously been specified with
- an array declarator.
-
- * New `-ffixed-line-length-N' option, where N is the maximum length
- of a typical fixed-form line, defaulting to 72 columns, such that
- characters beyond column N are ignored, or N is `none', meaning no
- characters are ignored. does not affect lines with `&' in column
- 1, which are always processed as if `-ffixed-line-length-none' was
- in effect.
-
- * No longer generate better code for some kinds of array references,
- as `gcc' back end is to be fixed to do this even better, and it
- turned out to slow down some code in some cases after all.
-
- * In `COMMON' and `EQUIVALENCE' areas with any members given initial
- values (e.g. via `DATA'), uninitialized members now always
- initialized to binary zeros (though this is not required by the
- standard, and might not be done in future versions of `g77').
- Previously, in some `COMMON'/`EQUIVALENCE' areas (essentially
- those with members of more than one type), the uninitialized
- members were initialized to spaces, to cater to `CHARACTER' types,
- but it seems no existing code expects that, while much existing
- code expects binary zeros.
-
-In 0.5.14:
-==========
-
- * Don't emit bad code when low bound of adjustable array is
- nonconstant and thus might vary as an expression at run time.
-
- * Emit correct code for calculation of number of trips in `DO' loops
- for cases where the loop should not execute at all. (This bug
- affected cases where the difference between the begin and end
- values was less than the step count, though probably not for
- floating-point cases.)
-
- * Fix crash when extra parentheses surround item in `DATA'
- implied-`DO' list.
-
- * Fix crash over minor internal inconsistencies in handling
- diagnostics, just substitute dummy strings where necessary.
-
- * Fix crash on some systems when compiling call to `MVBITS()'
- intrinsic.
-
- * Fix crash on array assignment `TYPEDDD(...)=...', where DDD is a
- string of one or more digits.
-
- * Fix crash on `DCMPLX()' with a single `INTEGER' argument.
-
- * Fix various crashes involving code with diagnosed errors.
-
- * Support `-I' option for `INCLUDE' statement, plus `gcc''s
- `header.gcc' facility for handling systems like MS-DOS.
-
- * Allow `INCLUDE' statement to be continued across multiple lines,
- even allow it to coexist with other statements on the same line.
-
- * Incorporate Bellcore fixes to `libf2c' through 1995-03-15--this
- fixes a bug involving infinite loops reading EOF with empty
- list-directed I/O list.
-
- * Remove all the `g77'-specific auto-configuration scripts, code,
- and so on, except for temporary substitutes for bsearch() and
- strtoul(), as too many configure/build problems were reported in
- these areas. People will have to fix their systems' problems
- themselves, or at least somewhere other than `g77', which expects
- a working ANSI C environment (and, for now, a GNU C compiler to
- compile `g77' itself).
-
- * Complain if initialized common redeclared as larger in subsequent
- program unit.
-
- * Warn if blank common initialized, since its size can vary and hence
- related warnings that might be helpful won't be seen.
-
- * New `-fbackslash' option, on by default, that causes `\' within
- `CHARACTER' and Hollerith constants to be interpreted a la GNU C.
- Note that this behavior is somewhat different from `f2c''s, which
- supports only a limited subset of backslash (escape) sequences.
-
- * Make `-fugly-args' the default.
-
- * New `-fugly-init' option, on by default, that allows
- typeless/Hollerith to be specified as initial values for variables
- or named constants (`PARAMETER'), and also allows
- character<->numeric conversion in those contexts--turn off via
- `-fno-ugly-init'.
-
- * New `-finit-local-zero' option to initialize local variables to
- binary zeros. This does not affect whether they are `SAVE'd, i.e.
- made automatic or static.
-
- * New `-Wimplicit' option to warn about implicitly typed variables,
- arrays, and functions. (Basically causes all program units to
- default to `IMPLICIT NONE'.)
-
- * `-Wall' now implies `-Wuninitialized' as with `gcc' (i.e. unless
- `-O' not specified, since `-Wuninitialized' requires `-O'), and
- implies `-Wunused' as well.
-
- * `-Wunused' no longer gives spurious messages for unused `EXTERNAL'
- names (since they are assumed to refer to block data program
- units, to make use of libraries more reliable).
-
- * Support `%LOC()' and `LOC()' of character arguments.
-
- * Support null (zero-length) character constants and expressions.
-
- * Support `f2c''s `IMAG()' generic intrinsic.
-
- * Support `ICHAR()', `IACHAR()', and `LEN()' of character
- expressions that are valid in assignments but not normally as
- actual arguments.
-
- * Support `f2c'-style `&' in column 1 to mean continuation line.
-
- * Allow `NAMELIST', `EXTERNAL', `INTRINSIC', and `VOLATILE' in
- `BLOCK DATA', even though these are not allowed by the standard.
-
- * Allow `RETURN' in main program unit.
-
- * Changes to Hollerith-constant support to obey Appendix C of the
- standard:
-
- - Now padded on the right with zeros, not spaces.
-
- - Hollerith "format specifications" in the form of arrays of
- non-character allowed.
-
- - Warnings issued when non-space truncation occurs when
- converting to another type.
-
- - When specified as actual argument, now passed by reference to
- `INTEGER' (padded on right with spaces if constant too small,
- otherwise fully intact if constant wider the `INTEGER' type)
- instead of by value.
-
- *Warning:* `f2c' differs on the interpretation of `CALL FOO(1HX)',
- which it treats exactly the same as `CALL FOO('X')', but which the
- standard and `g77' treat as `CALL FOO(%REF('X '))' (padded with
- as many spaces as necessary to widen to `INTEGER'), essentially.
-
- * Changes and fixes to typeless-constant support:
-
- - Now treated as a typeless double-length `INTEGER' value.
-
- - Warnings issued when overflow occurs.
-
- - Padded on the left with zeros when converting to a larger
- type.
-
- - Should be properly aligned and ordered on the target machine
- for whatever type it is turned into.
-
- - When specified as actual argument, now passed as reference to
- a default `INTEGER' constant.
-
- * `%DESCR()' of a non-`CHARACTER' expression now passes a pointer to
- the expression plus a length for the expression just as if it were
- a `CHARACTER' expression. For example, `CALL FOO(%DESCR(D))',
- where `D' is `REAL*8', is the same as `CALL FOO(D,%VAL(8)))'.
-
- * Name of multi-entrypoint master function changed to incorporate
- the name of the primary entry point instead of a decimal value, so
- the name of the master function for `SUBROUTINE X' with alternate
- entry points is now `__g77_masterfun_x'.
-
- * Remove redundant message about zero-step-count `DO' loops.
-
- * Clean up diagnostic messages, shortening many of them.
-
- * Fix typo in `g77' man page.
-
- * Clarify implications of constant-handling bugs in `f/BUGS'.
-
- * Generate better code for `**' operator with a right-hand operand of
- type `INTEGER'.
+ 30. Upgrade to `libf2c' as of 1998-06-18.
- * Generate better code for `SQRT()' and `DSQRT()', also when
- `-ffast-math' specified, enable better code generation for `SIN()'
- and `COS()'.
+ 31. Improve documentation and indexing.
- * Generate better code for some kinds of array references.
+In previous versions:
+=====================
- * Speed up lexing somewhat (this makes the compilation phase
- noticeably faster).
+ Information on previous versions is not provided in this
+`egcs/gcc/f/NEWS' file, to keep it short. See `egcs/gcc/f/news.texi',
+or any of its other derivations (Info, HTML, dvi forms) for such
+information.