Hello,
I'm working on building guile 2.2.4 for Cygwin/Windows. I have
now resolved a couple of library issues, and have run into a
problem with conflicting declarations.
Environment:
Cygwin
$ gcc --version
gcc (GCC) 7.4.0
Copyright © 2017 Free Software Foundation, Inc.
guile-2.2.4
gc-8.0.4
Error message:
make all-am
make[3]: Entering directory '/tmp/guile-2.2.4/libguile'
CC guile-guile.o
In file included from ../libguile.h:81:0,
from guile.c:34:
../libguile/pairs.h:182:1: error: conflicting types for
'GC_is_heap_ptr'
GC_is_heap_ptr (void *ptr)
^~~~~~~~~~~~~~
In file included from ../libguile/bdw-gc.h:47:0,
from ../libguile/gc.h:156,
from ../libguile/atomic.h:25,
from ../libguile.h:37,
from guile.c:34:
/usr/local/include/gc/gc.h:551:20: note: previous declaration of
'GC_is_heap_ptr' was here
GC_API int GC_CALL GC_is_heap_ptr(const void *);
^~~~~~~~~~~~~~
make[3]: *** [Makefile:3575: guile-guile.o] Error 1
make[3]: Leaving directory '/tmp/guile-2.2.4/libguile'
Analysis:
This appears to be a simple problem with the the function
GC_is_heap_ptr declared in two different ways in two different
files: /usr/local/include/gc/gc.h.156 and
/tmp/guile/2.2.4/libguile/pairs.h. The first file declares it as
"GC_API int GC_CALL GC_is_heap_ptr(const void *);", and the
second as "static int
GC_is_heap_ptr (void *ptr)
{
return GC_base (ptr) != NULL;
}
".
Proposed solution:
The obvious solution would be to surround the definition in
libguile/pairs.h with a conditional #ifndef HAVE_GC_IS_HEAP_PTR,
but i get the impression that libguile/pairs.h is
auto-generated, so I might brake your code. What would be your
preferred solution?
With my best regards,
--
Sören Jonsson
Kärnvägen 237
906 27 UMEÅ
SWEDEN
Tel: 090-180 339, 070-603 3896