Using and Porting GNU CC

7.5: Problems Compiling Certain Programs

• Parse errors may occur compiling X11 on a Decstation running Ultrix 4.2 because of problems in DEC's versions of the X11 header files `X11/Xlib.h' and `X11/Xutil.h'. People recommend adding `-I/usr/include/mit' to use the MIT versions of the header files, using the `-traditional' switch to turn off ANSI C, or fixing the header files by adding this:

  #ifdef __STDC__
  #define NeedFunctionPrototypes 0
  #endif
  

• If you have trouble compiling Perl on a SunOS 4 system, it may be because Perl specifies `-I/usr/ucbinclude'. This accesses the unfixed header files. Perl specifies the options

  -traditional -Dvolatile=__volatile__
  -I/usr/include/sun -I/usr/ucbinclude
  -fpcc-struct-return
  

  most of which are unnecessary with GCC 2.4.5 and newer versions. You can make a properly working Perl by setting ccflags to `-fwritable-strings' (implied by the `-traditional' in the original options) and cppflags to empty in `config.sh', then typing `./doSH; make depend; make'.

• On various 386 Unix systems derived from System V, including SCO, ISC, and ESIX, you may get error messages about running out of virtual memory while compiling certain programs.

  You can prevent this problem by linking GNU CC with the GNU malloc (which thus replaces the malloc that comes with the system). GNU malloc is available as a separate package, and also in the file `src/gmalloc.c' in the GNU Emacs 19 distribution.

  If you have installed GNU malloc as a separate library package, use this option when you relink GNU CC:

  MALLOC=/usr/local/lib/libgmalloc.a 
  

  Alternatively, if you have compiled `gmalloc.c' from Emacs 19, copy the object file to `gmalloc.o' and use this option when you relink GNU CC:

  MALLOC=gmalloc.o