SIGSTKSZ is now a run-time variable

[Carol Bouchard]

M4 Maintainers:

I work on a test system for distro testing.  I need to build newer Fedora images

before they are released to public.  A change that was introduced is the

#define SIGSTKSZ is no longer a statically defined variable.  It's value can

only be determined at run time.

# define SIGSTKSZ sysconf (_SC_SIGSTKSZ)

This affects m4 code since the code assumes a statically defined variable which

can be determined at preprocessor time.  As a result, the m4 code no longer compiles. 

/usr/include/signal.h:315,

                 from ./signal.h:52,
                 from c-stack.c:49:
c-stack.c:55:26: error: missing binary operator before token "("
   55 | #elif HAVE_LIBSIGSEGV && SIGSTKSZ < 16384
      |                          ^~~~~~~~

I am using m4-1.4.18 with compiler gcc (GCC) 10.2.1 20201125 (Red Hat 10.2.1-9).

Please advise how I can get past this.  It doesn't look like a simple change.  Do you

already have a patch available for this?

Carol