The isnan test suite verifies that isnan() is a macro, not only a function.
This test fails on OSF/1 5.1 with gcc:
depbase=`echo test-isnan.o | sed 's|[^/]*$|.deps/&|;s|\.o$||'`; gcc -std=gnu99
-DHAVE_CONFIG_H -I. -DGNULIB_STRICT_CHECKING=1 -I. -I. -I.. -I./..
-I../gllib -I./../gllib -Wall -mieee -g -O2 -MT test-isnan.o -MD -MP -MF
$depbase.Tpo -c -o test-isnan.o test-isnan.c && mv -f $depbase.Tpo $depbase.Po
test-isnan.c:26:3: error: #error missing declaration
*** Exit 1
Gary has reported this error also for Solaris.
This fixes it:
2010-12-19 Bruno Haible <br...@clisp.org>
isnan: Ensure it is a macro.
* lib/math.in.h (isnan): Define as a macro if not already a macro.
* doc/posix-functions/isnan.texi: Mention problem on IRIX, OSF/1,
Solaris.
--- doc/posix-functions/isnan.texi.orig Mon Dec 20 03:27:15 2010
+++ doc/posix-functions/isnan.texi Mon Dec 20 03:27:01 2010
@@ -12,6 +12,9 @@
@code{isnan} was introduced with C99 and is thus commonly not present
on pre-C99 systems.
@item
+...@code{isnan} is not a macro on some platforms:
+IRIX 6.5, OSF/1 5.1 with gcc, Solaris 11 2010-11.
+...@item
On IRIX 6.5 with @code{cc}, @code{isnan} does not recognize some NaNs.
@item
On NetBSD/i386 and glibc/ia64, @code{isnan} does not recognize some
--- lib/math.in.h.orig Mon Dec 20 03:27:15 2010
+++ lib/math.in.h Mon Dec 20 03:06:33 2010
@@ -680,6 +680,10 @@
sizeof (x) == sizeof (double) ? gl_isnan_d (x) : \
gl_isnan_f (x))
# endif
+/* Ensure isnan is a macro. */
+# ifndef isnan
+# define isnan isnan
+# endif
#elif defined GNULIB_POSIXCHECK
# if defined isnan
_GL_WARN_REAL_FLOATING_DECL (isnan);
