-
-@node Collect2
-@section @code{collect2}
-
-GNU CC uses a utility called @code{collect2} on nearly all systems to arrange
-to call various initialization functions at start time.
-
-The program @code{collect2} works by linking the program once and
-looking through the linker output file for symbols with particular names
-indicating they are constructor functions. If it finds any, it
-creates a new temporary @samp{.c} file containing a table of them,
-compiles it, and links the program a second time including that file.
-
-@findex __main
-@cindex constructors, automatic calls
-The actual calls to the constructors are carried out by a subroutine
-called @code{__main}, which is called (automatically) at the beginning
-of the body of @code{main} (provided @code{main} was compiled with GNU
-CC)@. Calling @code{__main} is necessary, even when compiling C code, to
-allow linking C and C++ object code together. (If you use
-@option{-nostdlib}, you get an unresolved reference to @code{__main},
-since it's defined in the standard GCC library. Include @option{-lgcc} at
-the end of your compiler command line to resolve this reference.)
-
-The program @code{collect2} is installed as @code{ld} in the directory
-where the passes of the compiler are installed. When @code{collect2}
-needs to find the @emph{real} @code{ld}, it tries the following file
-names:
-
-@itemize @bullet
-@item
-@file{real-ld} in the directories listed in the compiler's search
-directories.
-
-@item
-@file{real-ld} in the directories listed in the environment variable
-@code{PATH}.
-
-@item
-The file specified in the @code{REAL_LD_FILE_NAME} configuration macro,
-if specified.
-
-@item
-@file{ld} in the compiler's search directories, except that
-@code{collect2} will not execute itself recursively.
-
-@item
-@file{ld} in @code{PATH}.
-@end itemize
-
-``The compiler's search directories'' means all the directories where
-@code{gcc} searches for passes of the compiler. This includes
-directories that you specify with @option{-B}.
-
-Cross-compilers search a little differently:
-
-@itemize @bullet
-@item
-@file{real-ld} in the compiler's search directories.
-
-@item
-@file{@var{target}-real-ld} in @code{PATH}.
-
-@item
-The file specified in the @code{REAL_LD_FILE_NAME} configuration macro,
-if specified.
-
-@item
-@file{ld} in the compiler's search directories.
-
-@item
-@file{@var{target}-ld} in @code{PATH}.
-@end itemize
-
-@code{collect2} explicitly avoids running @code{ld} using the file name
-under which @code{collect2} itself was invoked. In fact, it remembers
-up a list of such names---in case one copy of @code{collect2} finds
-another copy (or version) of @code{collect2} installed as @code{ld} in a
-second place in the search path.
-
-@code{collect2} searches for the utilities @code{nm} and @code{strip}
-using the same algorithm as above for @code{ld}.
-
-@node Header Dirs
-@section Standard Header File Directories
-
-@code{GCC_INCLUDE_DIR} means the same thing for native and cross. It is
-where GNU CC stores its private include files, and also where GNU CC
-stores the fixed include files. A cross compiled GNU CC runs
-@code{fixincludes} on the header files in @file{$(tooldir)/include}.
-(If the cross compilation header files need to be fixed, they must be
-installed before GNU CC is built. If the cross compilation header files
-are already suitable for ISO C and GNU CC, nothing special need be
-done).
-
-@code{GPLUSPLUS_INCLUDE_DIR} means the same thing for native and cross. It
-is where @code{g++} looks first for header files. The C++ library
-installs only target independent header files in that directory.
-
-@code{LOCAL_INCLUDE_DIR} is used only by native compilers. GNU CC
-doesn't install anything there. It is normally
-@file{/usr/local/include}. This is where local additions to a packaged
-system should place header files.
-
-@code{CROSS_INCLUDE_DIR} is used only by cross compilers. GNU CC
-doesn't install anything there.
-
-@code{TOOL_INCLUDE_DIR} is used for both native and cross compilers. It
-is the place for other packages to install header files that GNU CC will
-use. For a cross-compiler, this is the equivalent of
-@file{/usr/include}. When you build a cross-compiler,
-@code{fixincludes} processes any header files in this directory.
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