X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;ds=sidebyside;f=m4%2Frintf.m4;h=ddd1a8270811d581d7fb9d4426f218e3c135282a;hb=dcf27bef48c9800d5a2be8349226f73f1b8ff2e5;hp=bb5f046147be821f41eb8e1879d8153c5c96c182;hpb=3c7d5d0cf885baa9add1cd34364fa1adfc459630;p=gnulib.git

diff --git a/m4/rintf.m4 b/m4/rintf.m4
index bb5f04614..ddd1a8270 100644
--- a/m4/rintf.m4
+++ b/m4/rintf.m4
@@ -1,5 +1,5 @@
-# rintf.m4 serial 2
-dnl Copyright (C) 2011 Free Software Foundation, Inc.
+# rintf.m4 serial 4
+dnl Copyright (C) 2011-2012 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
 dnl with or without modifications, as long as this notice is preserved.
@@ -8,11 +8,26 @@ AC_DEFUN([gl_FUNC_RINTF],
 [
   AC_REQUIRE([gl_MATH_H_DEFAULTS])
 
+  dnl Persuade glibc <math.h> to declare rintf().
+  AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
+
   dnl Determine RINTF_LIBM.
-  gl_MATHFUNC([rintf], [float], [(float)])
-  if test $gl_cv_func_rintf_no_libm = no \
-     && test $gl_cv_func_rintf_in_libm = no; then
+  gl_MATHFUNC([rintf], [float], [(float)],
+    [extern
+     #ifdef __cplusplus
+     "C"
+     #endif
+     float rintf (float);
+    ])
+  if test $gl_cv_func_rintf_no_libm = yes \
+     || test $gl_cv_func_rintf_in_libm = yes; then
+    HAVE_RINTF=1
+    dnl Also check whether it's declared.
+    dnl IRIX 6.5 has rintf() in libm but doesn't declare it in <math.h>.
+    AC_CHECK_DECLS([rintf], , [HAVE_DECL_RINTF=0], [[#include <math.h>]])
+  else
     HAVE_RINTF=0
+    HAVE_DECL_RINTF=0
     RINTF_LIBM=
   fi
   AC_SUBST([RINTF_LIBM])