X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/557002cf8162a0073dbc7050732cb6d75e184148..3ea19afd1f1bc05e32fb8b08d208932ab34545ef:/configure.in

diff --git a/configure.in b/configure.in
index 34f53337e8..e8d9a90e68 100644
--- a/configure.in
+++ b/configure.in
@@ -3619,14 +3619,9 @@ dnl ---------------------------------------------------------------------------
         fi
     elif test "$wxUSE_MSW" = 1; then
 dnl ---------------------------------------------------------------------------
-dnl DirectDraw  / Multimon for MSW
+dnl DirectDraw for MSW - optionally used by WxDisplay.
 dnl ---------------------------------------------------------------------------
-        AC_CHECK_HEADERS([multimon.h ddraw.h], [],
-            [
-                wxUSE_DISPLAY="no"
-                AC_MSG_WARN([ddraw.h or multimon.h not found; disabling wxDisplay])
-            ],
-            [#include <windows.h>])
+        AC_CHECK_HEADERS([ddraw.h], [], [], [#include <windows.h>])
     fi
 fi
 
@@ -5147,7 +5142,19 @@ if test "$wxUSE_OPTIMISE" = "no" ; then
     fi
 else
     if test "$GCC" = yes ; then
-        OPTIMISE_CFLAGS="-O2"
+        case "${host}" in
+            *-pc-os2_emx | *-pc-os2-emx )
+                dnl Not all of the supported gcc versions understand
+                dnl -fstrict-aliasing and none actually needs it (yet).
+                OPTIMISE_CFLAGS="-O2"
+            ;;
+            *)
+                dnl Switch on optimisation but keep strict-aliasing off for
+                dnl now (see -fstrict-aliasing in the gcc manual). When it is
+                dnl switched back on consider using -Wstrict-aliasing=2.
+                OPTIMISE_CFLAGS="-O2 -fno-strict-aliasing"
+            ;;
+        esac
     else
         OPTIMISE_CFLAGS="-O"
     fi