New module 'hypotl'.

[gnulib.git] / m4 / hypotl.m4

diff --git a/m4/hypotl.m4 b/m4/hypotl.m4
new file mode 100644 (file)
index 0000000..57b472f
--- /dev/null
+++ b/m4/hypotl.m4
@@ -0,0 +1,54 @@
+# hypotl.m4 serial 1
+dnl Copyright (C) 2012 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.
+
+AC_DEFUN([gl_FUNC_HYPOTL],
+[
+  AC_REQUIRE([gl_MATH_H_DEFAULTS])
+  AC_REQUIRE([gl_FUNC_HYPOT])
+
+  dnl Test whether hypotl() exists. Assume that hypotl(), if it exists, is
+  dnl defined in the same library as hypot().
+  save_LIBS="$LIBS"
+  LIBS="$LIBS $HYPOT_LIBM"
+  AC_CHECK_FUNCS([hypotl])
+  LIBS="$save_LIBS"
+  if test $ac_cv_func_hypotl = yes; then
+    HYPOTL_LIBM="$HYPOT_LIBM"
+  else
+    HAVE_HYPOTL=0
+    dnl Find libraries needed to link lib/hypotl.c.
+    if test $HAVE_SAME_LONG_DOUBLE_AS_DOUBLE = 1; then
+      HYPOTL_LIBM="$HYPOT_LIBM"
+    else
+      AC_REQUIRE([gl_FUNC_FABSL])
+      AC_REQUIRE([gl_FUNC_FREXPL])
+      AC_REQUIRE([gl_FUNC_LDEXPL])
+      AC_REQUIRE([gl_FUNC_SQRTL])
+      HYPOTL_LIBM=
+      dnl Append $FABSL_LIBM to HYPOTL_LIBM, avoiding gratuitous duplicates.
+      case " $HYPOTL_LIBM " in
+        *" $FABSL_LIBM "*) ;;
+        *) HYPOTL_LIBM="$HYPOTL_LIBM $FABSL_LIBM" ;;
+      esac
+      dnl Append $FREXPL_LIBM to HYPOTL_LIBM, avoiding gratuitous duplicates.
+      case " $HYPOTL_LIBM " in
+        *" $FREXPL_LIBM "*) ;;
+        *) HYPOTL_LIBM="$HYPOTL_LIBM $FREXPL_LIBM" ;;
+      esac
+      dnl Append $LDEXPL_LIBM to HYPOTL_LIBM, avoiding gratuitous duplicates.
+      case " $HYPOTL_LIBM " in
+        *" $LDEXPL_LIBM "*) ;;
+        *) HYPOTL_LIBM="$HYPOTL_LIBM $LDEXPL_LIBM" ;;
+      esac
+      dnl Append $SQRTL_LIBM to HYPOTL_LIBM, avoiding gratuitous duplicates.
+      case " $HYPOTL_LIBM " in
+        *" $SQRTL_LIBM "*) ;;
+        *) HYPOTL_LIBM="$HYPOTL_LIBM $SQRTL_LIBM" ;;
+      esac
+    fi
+  fi
+  AC_SUBST([HYPOTL_LIBM])
+])