X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=m4%2Fhypot.m4;h=2ae3be7a9b2ca6b3de30acfa2cbfd0c672d3e3a0;hb=43593319b31e6b0175b8eec4433bac744959822d;hp=52df05f32dd940e17f5567c428cece8f2325d38b;hpb=bf6909e5ca400414ed0730b7f64e48d04993936e;p=gnulib.git

diff --git a/m4/hypot.m4 b/m4/hypot.m4
index 52df05f32..2ae3be7a9 100644
--- a/m4/hypot.m4
+++ b/m4/hypot.m4
@@ -1,5 +1,5 @@
-# hypot.m4 serial 3
-dnl Copyright (C) 2012 Free Software Foundation, Inc.
+# hypot.m4 serial 4
+dnl Copyright (C) 2012-2013 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.
@@ -17,6 +17,7 @@ AC_DEFUN([gl_FUNC_HYPOT],
 
   m4_ifdef([gl_FUNC_HYPOT_IEEE], [
     if test $gl_hypot_required = ieee && test $REPLACE_HYPOT = 0; then
+      AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
       AC_CACHE_CHECK([whether hypot works according to ISO C 99 with IEC 60559],
         [gl_cv_func_hypot_ieee],
         [
@@ -53,7 +54,13 @@ int main (int argc, char *argv[])
             ]])],
             [gl_cv_func_hypot_ieee=yes],
             [gl_cv_func_hypot_ieee=no],
-            [gl_cv_func_hypot_ieee="guessing no"])
+            [case "$host_os" in
+                       # Guess yes on glibc systems.
+               *-gnu*) gl_cv_func_hypot_ieee="guessing yes" ;;
+                       # If we don't know, assume the worst.
+               *)      gl_cv_func_hypot_ieee="guessing no" ;;
+             esac
+            ])
           LIBS="$save_LIBS"
         ])
       case "$gl_cv_func_hypot_ieee" in