strsignal: fix compilation error

[Bruno Haible]

On IRIX 6.5, the strsignal replacement fails to compile:

"strsignal.c", line 69: error(1143): declaration is incompatible with
          "char *_sys_siglist[]" (declared at line 176 of
          "///usr/include/signal.h")
  static const char *_sys_siglist[NSIG];
                     ^

"strsignal.c", line 150: error(1166): expected a declaration
  } while (0);
    ^

This should fix it:


2008-04-11  Bruno Haible  <address@hidden>

        * lib/strsignal.c (_sys_siglist): Don't declare if already declared.
        (init): Fix syntax error.
        * m4/strsignal.m4 (gl_PREREQ_STRSIGNAL): Check whether _sys_siglist
        is declared.

--- lib/strsignal.c.orig        2008-04-12 01:32:35.000000000 +0200
+++ lib/strsignal.c     2008-04-12 01:32:32.000000000 +0200
@@ -66,7 +66,9 @@
 #  ifndef NSIG
 #   define NSIG 32
 #  endif /* NSIG */
+#  if !HAVE_DECL__SYS_SIGLIST
 static const char *_sys_siglist[NSIG];
+#  endif
 # endif /* !HAVE_DECL_SYS_SIGLIST */
 
 #endif /* _LIBC */
@@ -147,7 +149,6 @@
 #  define init_sig(sig, abbrev, desc) \
   if (sig >= 0 && sig < NSIG) \
     _sys_siglist[sig] = desc;
-} while (0);
 
 #  include "siglist.h"
 
--- m4/strsignal.m4.orig        2008-04-12 01:32:35.000000000 +0200
+++ m4/strsignal.m4     2008-04-12 01:29:14.000000000 +0200
@@ -1,4 +1,4 @@
-# strsignal.m4 serial 2
+# strsignal.m4 serial 3
 dnl Copyright (C) 2008 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -51,5 +51,5 @@
 # Prerequisites of lib/strsignal.c.
 AC_DEFUN([gl_PREREQ_STRSIGNAL], [
   AC_REQUIRE([AC_DECL_SYS_SIGLIST])
-  :
+  AC_CHECK_DECLS([_sys_siglist], [], [], [#include <signal.h>])
 ])