configure: Don't special case Cygwin to use gnu99, define _XOPEN_SOURCE instead

Revert "build: Build on Cygwin with gnu99 instead of c99." and define
_XOPEN_SOURCE appropriately.

This reverts commit 53e36d333c9b619c1a5fe9a8d2d08665654b0234.

Since Cygwin 1.7.18 (April 2013), it's headers correctly prototype strtoll()
when using -std=c99, and correctly prototype strdup() when _XOPEN_SOURCE is
defined appropriately, so this workaround is no longer needed.

Signed-off-by: Jon TURNEY <jon.turney@dronecode.org.uk>
Cc: Vinson Lee <vlee@freedesktop.org>

diff --git a/configure.ac b/configure.ac
index 4646212..701223b 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -159,20 +159,13 @@ solaris*)
     DEFINES="$DEFINES -DHAVE_PTHREAD -DSVR4"
     ;;
 cygwin*)
-    DEFINES="$DEFINES -DHAVE_PTHREAD"
+    DEFINES="$DEFINES -D_XOPEN_SOURCE=500 -DHAVE_PTHREAD"
     ;;
 esac
 
 dnl Add flags for gcc and g++
 if test "x$GCC" = xyes; then
-    case "$host_os" in
-    cygwin*)
-        CFLAGS="$CFLAGS -Wall -std=gnu99"
-        ;;
-    *)
-        CFLAGS="$CFLAGS -Wall -std=c99"
-        ;;
-    esac
+    CFLAGS="$CFLAGS -Wall -std=c99"
 
     # Enable -Werror=implicit-function-declaration and
     # -Werror=missing-prototypes, if available, or otherwise, just