m4/inttypes.m4: announce test + caching

[Ralf Wildenhues]

What do you think of the following patch?  This looks useful to me for
nailing down an independent issue in lib/inttypes_.h: with this, it
actually works to override the test temporarily with
  ./configure gl_cv_header_working_inttypes_h=yes

(and thus decouple this from other build failures).

Cheers,
Ralf

2006-11-14  Ralf Wildenhues  <address@hidden>

        * m4/inttypes.m4 (gl_INTTYPES_H): Use AC_CACHE_CHECK so that the
        test for conforming inttypes.h is both announced and cached.

Index: m4/inttypes.m4
===================================================================
RCS file: /cvsroot/gnulib/gnulib/m4/inttypes.m4,v
retrieving revision 1.15
diff -u -r1.15 inttypes.m4
--- m4/inttypes.m4      18 Sep 2006 19:23:59 -0000      1.15
+++ m4/inttypes.m4      14 Nov 2006 18:46:18 -0000
@@ -1,4 +1,4 @@
-# inttypes.m4 serial 5
+# inttypes.m4 serial 6
 dnl Copyright (C) 2006 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -22,15 +22,18 @@
   dnl   - the existence of an <inttypes.h>,
   dnl   - that imaxabs, imaxdiv, strtoimax, strtoumax are declared,
   dnl   - some additional tests.
-  gl_cv_header_working_inttypes_h=no
-  if test "$gl_cv_header_working_stdint_h" = yes \
-     && test $ac_cv_header_inttypes_h = yes \
-     && test "$ac_cv_have_decl_imaxabs" = yes \
-     && test "$ac_cv_have_decl_imaxdiv" = yes \
-     && test "$ac_cv_have_decl_strtoimax" = yes \
-     && test "$ac_cv_have_decl_strtoumax" = yes; then
-    AC_COMPILE_IFELSE([
-      AC_LANG_PROGRAM([
+  AC_CACHE_CHECK([whether inttypes.h conforms to C99],
+                 [gl_cv_header_working_inttypes_h],
+  [
+    gl_cv_header_working_inttypes_h=no
+    if test "$gl_cv_header_working_stdint_h" = yes \
+       && test $ac_cv_header_inttypes_h = yes \
+       && test "$ac_cv_have_decl_imaxabs" = yes \
+       && test "$ac_cv_have_decl_imaxdiv" = yes \
+       && test "$ac_cv_have_decl_strtoimax" = yes \
+       && test "$ac_cv_have_decl_strtoumax" = yes; then
+      AC_COMPILE_IFELSE([
+        AC_LANG_PROGRAM([
 #include <stddef.h>
 #define __STDC_LIMIT_MACROS 1 /* to make it work also in C++ mode */
 #define __STDC_CONSTANT_MACROS 1 /* to make it work also in C++ mode */
@@ -128,9 +131,9 @@
   SCNoPTR SCNuPTR SCNxPTR
 #endif
   ;
-      ])],
-      [gl_cv_header_working_inttypes_h=yes])
-  fi
+        ])],
+        [gl_cv_header_working_inttypes_h=yes])
+    fi])
   if test $gl_cv_header_working_inttypes_h = yes; then
     dnl Use the existing <inttypes.h>.
     INTTYPES_H=''