maint: update copyright

[gnulib.git] / m4 / cbrtf.m4

diff --git a/m4/cbrtf.m4 b/m4/cbrtf.m4
index cf2c6b7..ad828ee 100644 (file)
--- a/m4/cbrtf.m4
+++ b/m4/cbrtf.m4
@@ -1,5 +1,5 @@
-# cbrtf.m4 serial 1
-dnl Copyright (C) 2012 Free Software Foundation, Inc.
+# cbrtf.m4 serial 3
+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.
@@ -9,6 +9,9 @@ AC_DEFUN([gl_FUNC_CBRTF],
   AC_REQUIRE([gl_MATH_H_DEFAULTS])
   AC_REQUIRE([gl_FUNC_CBRT])
 
+  dnl Persuade glibc <math.h> to declare cbrtf().
+  AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
+
   dnl Test whether cbrtf() exists. Assume that cbrtf(), if it exists, is
   dnl defined in the same library as cbrt().
   save_LIBS="$LIBS"
@@ -20,9 +23,19 @@ AC_DEFUN([gl_FUNC_CBRTF],
     dnl Also check whether it's declared.
     dnl IRIX 6.5 has cbrtf() in libm but doesn't declare it in <math.h>.
     AC_CHECK_DECL([cbrtf], , [HAVE_DECL_CBRTF=0], [[#include <math.h>]])
+    save_LIBS="$LIBS"
+    LIBS="$LIBS $CBRTF_LIBM"
+    gl_FUNC_CBRTF_WORKS
+    LIBS="$save_LIBS"
+    case "$gl_cv_func_cbrtf_works" in
+      *yes) ;;
+      *) REPLACE_CBRTF=1 ;;
+    esac
   else
     HAVE_CBRTF=0
     HAVE_DECL_CBRTF=0
+  fi
+  if test $HAVE_CBRTF = 0 || test $REPLACE_CBRTF = 1; then
     dnl Find libraries needed to link lib/cbrtf.c.
     AC_REQUIRE([gl_FUNC_FABSF])
     AC_REQUIRE([gl_FUNC_FREXPF])
@@ -46,3 +59,41 @@ AC_DEFUN([gl_FUNC_CBRTF],
   fi
   AC_SUBST([CBRTF_LIBM])
 ])
+
+dnl Test whether cbrtf() works.
+dnl It returns wrong values on IRIX 6.5.
+AC_DEFUN([gl_FUNC_CBRTF_WORKS],
+[
+  AC_REQUIRE([AC_PROG_CC])
+  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
+  AC_CACHE_CHECK([whether cbrtf works], [gl_cv_func_cbrtf_works],
+    [
+      AC_RUN_IFELSE(
+        [AC_LANG_SOURCE([[
+#include <math.h>
+volatile float x;
+volatile float y;
+int main ()
+{
+  extern
+  #ifdef __cplusplus
+  "C"
+  #endif
+  float cbrtf (float);
+  /* This test fails on IRIX 6.5.  */
+  x = - 0.0f;
+  y = cbrtf (x);
+  if (!(y == 0.0f))
+    return 1;
+  return 0;
+}
+]])],
+        [gl_cv_func_cbrtf_works=yes],
+        [gl_cv_func_cbrtf_works=no],
+        [case "$host_os" in
+           irix*) gl_cv_func_cbrtf_works="guessing no";;
+           *)     gl_cv_func_cbrtf_works="guessing yes";;
+         esac
+        ])
+    ])
+])