[gtk+] Bug 676087-configure.ac: isnan() and isinf() are macros, not functions

[Matthias Clasen <matthiasc src gnome org>]

commit d6aee922bb5da8254fafdf605951cf5b0150537d
Author: Natanael Copa <ncopa alpinelinux org>
Date:   Tue May 15 13:09:24 2012 +0200

    Bug 676087-configure.ac: isnan() and isinf() are macros, not functions
    
    The isnan() and isinf() are C99 macros not functions so use
    AC_CHECK_DECL instead of AC_CHECK_FUNCS for those.

 configure.ac       |    3 ++-
 gdk/fallback-c89.c |    4 ++--
 2 files changed, 4 insertions(+), 3 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 857d015..c801dd2 100644
--- a/configure.ac
+++ b/configure.ac
@@ -751,7 +751,8 @@ AC_TYPE_UID_T
 
 # Check for round(), rint(), isnan(), isinf() and nearbyint()
 AC_CHECK_LIB(m,round,,)
-AC_CHECK_FUNCS(round rint isnan isinf nearbyint)
+AC_CHECK_FUNCS(round rint nearbyint)
+AC_CHECK_DECLS([isnan, isinf], [], [], [[#include <math.h>]])
 
 # Checks for gdkspawn
 AC_CHECK_HEADERS(crt_externs.h)
diff --git a/gdk/fallback-c89.c b/gdk/fallback-c89.c
index 35dea77..b150044 100644
--- a/gdk/fallback-c89.c
+++ b/gdk/fallback-c89.c
@@ -19,7 +19,7 @@
 
 #include <float.h>
 
-#ifndef HAVE_ISNAN
+#ifndef HAVE_DECL_ISNAN
 /* it seems of the supported compilers only
  * MSVC does not have isnan(), but it does
  * have _isnan() which does the same as isnan()
@@ -31,7 +31,7 @@ isnan (double x)
 }
 #endif
 
-#ifndef HAVE_ISINF
+#ifndef HAVE_DECL_ISINF
 /* Unfortunately MSVC does not have finite()
  * but it does have _finite() which is the same
  * as finite() except when x is a NaN