FreeBSD may not have the C99 long double math interfaces.

(This sanity logic could migrated to Configure)

1 files changed, 33 insertions, 0 deletions

diff --git a/hints/freebsd.sh b/hints/freebsd.sh
index a67c0bbb18..673dc4bade 100644
--- a/hints/freebsd.sh
+++ b/hints/freebsd.sh
@@ -309,3 +309,36 @@ esac
 # Meanwhile, the following workaround should be safe on all versions
 # of FreeBSD.
 d_printf_format_null='undef'
+
+$cat > UU/uselongdouble.cbu <<'EOCBU'
+# This script UU/uselongdouble.cbu will get 'called-back' by Configure
+# after it has prompted the user for whether to use long doubles.
+
+# Some FreeBSD releases apparently don't really have the C99 long double
+# versions of math functions.  If this seems to be the case, disable
+# uselongdouble.
+#
+# XXX This sanity check logic could be move to Configure.
+case "$uselongdouble" in
+define)
+  echo "Checking if your long double math functions work right..." >&4
+  cat > ldblm$$.c <<EOF
+#include <math.h>
+#include <stdio.h>
+int main() {
+  printf("%Lg\n", sqrtl(logl(expl(1.0L))+powl(2.0L, 3.0L))+cosl(sinl(1.0L)));
+}
+EOF
+  $cc -o ldblm$$ ldblm$$.c -lm
+  case `test -x ldblm$$ && ./ldblm$$` in
+  4) echo "Your long double math functions are working correctly." >&4 ;;
+  *)
+    echo "Your long double math functions are broken, disabling uselongdouble." >&4
+    uselongdouble=$undef
+    ;;
+  esac
+  rm -f ldblm$$.c ldblm$$
+  ;;
+esac
+
+EOCBU