Hi Bruno, there is one more issue with c-stack when all warnings are enabled (and the DEBUG flag is set):
c-stack.c: In function ‘segv_handler’: c-stack.c:175:5: warning: ignoring return value of ‘write’, declared with attribute warn_unused_result [-Wunused-result] 175 | write (STDERR_FILENO, buf, strlen (buf)); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ c-stack.c: In function ‘overflow_handler’: c-stack.c:198:5: warning: ignoring return value of ‘write’, declared with attribute warn_unused_result [-Wunused-result] 198 | write (STDERR_FILENO, buf, strlen (buf)); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ This will be a nice use case for the newly created attribute module and MAYBE_UNUSED. Thanks, Marc Am Sa., 9. Mai 2020 um 13:34 Uhr schrieb Bruno Haible <br...@clisp.org>: > > Hi Marc, > > > Please add > > > > #ifdef DEBUG > > # include <stdio.h> > > #endif > > > > at the beginning of c-stack.c. > > > > When the DEBUG flag is enabled, c-stack.c uses sprintf and without the > > suggested addition gcc complains about an implicit declaration of the > > function sprintf. > > Yup. Thanks for the suggestion. Done. > > > 2020-05-09 Bruno Haible <br...@clisp.org> > > c-stack: Fix warning when DEBUG is enabled. > Patch suggested by Marc Nieper-Wißkirchen <marc.nieper+...@gmail.com> > in > <https://lists.gnu.org/archive/html/bug-gnulib/2020-05/msg00081.html>. > * lib/c-stack.c: Include <stdio.h>. > > diff --git a/lib/c-stack.c b/lib/c-stack.c > index 4050d08..e486591 100644 > --- a/lib/c-stack.c > +++ b/lib/c-stack.c > @@ -65,6 +65,10 @@ typedef struct sigaltstack stack_t; > > #include <unistd.h> > > +#if DEBUG > +# include <stdio.h> > +#endif > + > #if HAVE_LIBSIGSEGV > # include <sigsegv.h> > #endif >