Re: Help with GCC on Cygwin

[Brian Dessent <brian at dessent dot net>]

"Balaji V. Iyer" wrote:

> ../gcc-4.0.2/configure --prefix=/home/Software_Tools/install
> --enable-languages="c"
> 
> Then I did: make all install

You really should just do "make" and verify that it works first, then do
"make install".

> Now it is failing somewhere in libiberty....(below I have hte errors)
> 
> Configuring in fixincludes
> configure: loading cache ./config.cache
> checking build system type... i686-pc-cygwin checking host system
> type... i686-pc-cygwin checking target system type... i686-pc-cygwin
> checking for i686-pc-cygwin-gcc... gcc checking for C compiler default

Munging the output like this really does make it a pain to try to follow
what's going on.

> Configuring in libiberty
> configure: creating cache ./config.cache checking whether to enable
> ...
> for sys/param.h... yes checking for limits.h... yes checking for

Note that libiberty's check for limits.h returned yes.  This means
HAVE_LIMITS_H should be set.  Verify this in config.status and config.h.

> ../../gcc-4.0.2/libiberty/regex.c:2477: warning: implicit declaration of
> function `free'

All of these 'implicit declaration' warnings are very disconcerting, it
implies that the headers are not being included due to HAVE_FOO_H not
being defined; or there is some kind of environmental problem.  You
should not have any of these implicit declaration warnings at all, it is
a sign of something broken.

> gcc -c -DHAVE_CONFIG_H -g -O2  -I.
> -I../../gcc-4.0.2/libiberty/../include  -W -Wall -Wtraditional -pedantic
> ../../gcc-4.0.2/libiberty/fibheap.c -o fibheap.o
> ../../gcc-4.0.2/libiberty/fibheap.c: In function `fibheap_delete_node':
> ../../gcc-4.0.2/libiberty/fibheap.c:285: error: `LONG_MIN' undeclared
> (first use in this function)
> ../../gcc-4.0.2/libiberty/fibheap.c:285: error: (Each undeclared
> identifier is reported only once

Cygwin's limits.h defines LONG_MIN.  Yet the configure check said it
found a working limits.h, and HAVE_LIMITS_H should be defined, which
means fibheap.c should have included limits.h.  You need to find out why
this is not working.  Look at the preprocessed source (add -save-temps
or -E to the above compilation command) of the file.  Look at config.h. 
Look at config.status.  Check that your Cygwin installation is sane by
the following testcase:

#include <limits.h>

int main(int argc, char **argv)
{
#ifndef LONG_MIN
  abort();
#endif
  return 0;
}

Normally none of this is an issue, you can simply "configure && make" to
build gcc in Cygwin without all these warnings.

Brian