NEWS.stable: log cherry-pick [e446f25]->[c092018] relocatable-shell: Update suggested...

[gnulib.git] / m4 / hypotf.m4

diff --git a/m4/hypotf.m4 b/m4/hypotf.m4
index b4ebe9e..38a5767 100644 (file)
--- a/m4/hypotf.m4
+++ b/m4/hypotf.m4
@@ -1,5 +1,5 @@
-# hypotf.m4 serial 3
-dnl Copyright (C) 2012 Free Software Foundation, Inc.
+# hypotf.m4 serial 4
+dnl Copyright (C) 2012-2014 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.
@@ -31,6 +31,7 @@ AC_DEFUN([gl_FUNC_HYPOTF],
     esac
     m4_ifdef([gl_FUNC_HYPOTF_IEEE], [
       if test $gl_hypotf_required = ieee && test $REPLACE_HYPOTF = 0; then
+        AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
         AC_CACHE_CHECK([whether hypotf works according to ISO C 99 with IEC 60559],
           [gl_cv_func_hypotf_ieee],
           [
@@ -67,7 +68,13 @@ int main (int argc, char *argv[])
               ]])],
               [gl_cv_func_hypotf_ieee=yes],
               [gl_cv_func_hypotf_ieee=no],
-              [gl_cv_func_hypotf_ieee="guessing no"])
+              [case "$host_os" in
+                         # Guess yes on glibc systems.
+                 *-gnu*) gl_cv_func_hypotf_ieee="guessing yes" ;;
+                         # If we don't know, assume the worst.
+                 *)      gl_cv_func_hypotf_ieee="guessing no" ;;
+               esac
+              ])
             LIBS="$save_LIBS"
           ])
         case "$gl_cv_func_hypotf_ieee" in