try to run configure in this directory. Follow the configuration
instructions in ../README.
-Please report bugs and fixes to "bug-gnu-utils@prep.ai.mit.edu". Thank you.
+Please report bugs to "gcc-bugs@gcc.gnu.org" and send fixes to
+"gcc-patches@gcc.gnu.org". Thank you.
ADDING A NEW FILE
=================
To add a new required file, edit Makefile to add the source file
name to CFILES and the object file to REQUIRED_OFILES.
-Adding a new optional file is more fragile. As a general rule,
-an optional file will be included in the library if it provides
-functionality missing in the "standard" C library.
-For most hosts, the Makefile automatically figures out which
-functionality is missing by compiling and linking a dummy test
-program, and examining the error messages.
-
-So to get this to work, you should do the following:
-
-1) Select one function defined in the file you're adding.
-For example, the getcwd function.
-2) Add that function to the list in the file functions.def.
-3) The name of the new file must be the same as the function
-you've chosen with the .c suffix added. E.g. getcwd() must be
-defined in getcwd.c. (The file can define other functions as well.)
-4) In Makefile.in, add the name of the source file (e.g. getcwd.c)
-to CFILES.
-
-The file you've added (e.g. getcwd.c) should compile and work
-on all hosts where it is needed (e.g. not found when linking
-the dummy.c program). It does not have to work or even
-compile on hosts where it is not needed.
+To add a new optional file, it must provide a single function, and the
+name of the function must be the same as the name of the file.
+
+ * Add the source file name to CFILES.
+
+ * Add the function to name to the funcs shell variable in
+ configure.ac.
-HOW THE AUTOMATIC CONFIGURATION WORKS
-=====================================
-
-The libiberty.a target (in RULE1) depends on $(DO_ALSO).
-For normal configurations, DO_ALSO=needed-list.
-
-So needed-list is first made. The needed-list rule compiles
-dummy.c. Because dummy.c includes functions.def, the
-resulting object file will contain a call to each of the
-optional functions (for simplicity assume each optional file
-defines a single function). This object file will be linked
-against the standard libraries (as defined by using $(CC)
-and various flags). Any function missing will causes the
-linker to emit an error message. We assume the name
-of the missing function(s) are in the error message(s).
-The awk script find-needed.awk has been generated from
-functions.def. It is used to search the linker output
-messages for words that match the functions listed in
-functions.def. The list of functions found is written
-on a single line to the file needed-list.
-
-After needed-list has been generated, the libiberty.a
-target (in RULE1) just calls 'make' recursively.
-It passes the contents of needed-list using the
-definition (expanded) HOST_OFILES="`cat needed-list`".
-It also tells the inferior 'make' to use RULE2.
-
-The inferior 'make' is very conventional: The main
-rule is $(RULE2) (which is libiberty.a). It depends
-on a list of object files: $(REQUIRED_OFILES) $(HOST_OFILES)
-(and $(EXTRA_OFILES), which is usually empty). The superior
-'make' passes in $(HOST_OFILES); the others are fixed
-in the Makefile.
+ * Add the function to the AC_CHECK_FUNCS lists just after the
+ setting of the funcs shell variable. These AC_CHECK_FUNCS calls
+ are never executed; they are there to make autoheader work
+ better.
+
+ * Consider the special cases of building libiberty; as of this
+ writing, the special cases are newlib and VxWorks. If a
+ particular special case provides the function, you do not need
+ to do anything. If it does not provide the function, add the
+ object file to LIBOBJS, and add the function name to the case
+ controlling whether to define HAVE_func.
+
+The optional file you've added (e.g. getcwd.c) should compile and work
+on all hosts where it is needed. It does not have to work or even
+compile on hosts where it is not needed.
ADDING A NEW CONFIGURATION
==========================
by with defining EXTRA_OFILES in your Makefile stub. This is
a list of object file names that should be treated as required
for this configuration - they will be included in libiberty.a,
-regardless of whatever might be in the C library. Moreover,
-when the dummy.c program is linked, it will be linked with
-$(EXTRA_OFILES). Therefore, if a function in functions.def
-is defined by one of the EXTRA_OFILES, it will not be listed as
-"needed". Thus if your hal9000 host needs a special implementation
-of getcwd, you can just create hal9000-getcwd.c, and define:
- EXTRA_OFILES=hal9000-getcwd.o
-Or if you want to use the libiberty version of strstr(),
-even though there is a version in the C library (it might be
-buggy or slow), just define:
- EXTRA_OFILES=strstr.o
-
-You can create a "manual" host configuration FOO with a file
-config/mh-FOO. In it, the HOST_OFILES macro should explicitly
-list that subset of the optional files that should be in the
-library. You should also set:
- DO_ALSO =
-This overrides all of the magic needed to automatically
-determine which files are "needed." However, keeping that list
-up to date is another matter...
-
-HOW THE MANUAL CONFIGURATION WORKS
-==================================
-
-This also uses a recursive make, but the superior make
-does not do anything interesting - it just calls the
-inferior make with HOST_OFILES defined as $(HOST_OFILES),
-which is the list you created in your configuration.
-
-You probably don't want to depend on manual configuration,
-because keeping the HOST_OFILES list up-to-date will be a pain.
+regardless of whatever might be in the C library.
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