Tweak message.

diff --git a/m4/isnanf.m4 b/m4/isnanf.m4
index 03ab66b1e8248b12cfe9a138f6253db6e1cc9866..d5575130299de08e821f69f3afb1aa5ed126603e 100644 (file)
--- a/m4/isnanf.m4
+++ b/m4/isnanf.m4
@@ -46,7 +46,7 @@ AC_DEFUN([gl_ISNANF_WORKS],
 [
   AC_REQUIRE([AC_PROG_CC])
   AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
-  AC_CACHE_CHECK([whether isnanf works], [gl_cv_func_isnanf_works],
+  AC_CACHE_CHECK([whether isnan(float) works], [gl_cv_func_isnanf_works],
     [
       AC_TRY_RUN([
 #include <math.h>