diff -r 69da99676239 -r ac3f5137f84d common/autoconf/platform.m4
--- a/common/autoconf/platform.m4	Fri Sep 13 13:07:02 2013 +0200
+++ b/common/autoconf/platform.m4	Fri Sep 13 14:59:23 2013 +0200
@@ -422,18 +422,21 @@
 # Add -mX to various FLAGS variables.
 AC_DEFUN([PLATFORM_SET_COMPILER_TARGET_BITS_FLAGS],
 [
-  # keep track of c/cxx flags that we added outselves...
-  #   to prevent emitting warning...
-  TARGET_BITS_FLAG="-m${OPENJDK_TARGET_CPU_BITS}"
-  AC_SUBST(TARGET_BITS_FLAG)
+  # When we add flags to the "official" CFLAGS etc, we need to
+  # keep track of these additions in ADDED_CFLAGS etc. These
+  # will later be checked to make sure only controlled additions
+  # have been made to CFLAGS etc.
+  ADDED_CFLAGS=" -m${OPENJDK_TARGET_CPU_BITS}"
+  ADDED_CXXFLAGS=" -m${OPENJDK_TARGET_CPU_BITS}"
+  ADDED_LDFLAGS=" -m${OPENJDK_TARGET_CPU_BITS}"
 
-  CFLAGS="${CFLAGS} ${TARGET_BITS_FLAG}"
-  CXXFLAGS="${CXXFLAGS} ${TARGET_BITS_FLAG}"
-  LDFLAGS="${LDFLAGS} ${TARGET_BITS_FLAG}"
+  CFLAGS="${CFLAGS}${ADDED_CFLAGS}"
+  CXXFLAGS="${CXXFLAGS}${ADDED_CXXFLAGS}"
+  LDFLAGS="${LDFLAGS}${ADDED_LDFLAGS}"
 
-  CFLAGS_JDK="${CFLAGS_JDK} ${TARGET_BITS_FLAG}"
-  CXXFLAGS_JDK="${CXXFLAGS_JDK} ${TARGET_BITS_FLAG}"
-  LDFLAGS_JDK="${LDFLAGS_JDK} ${TARGET_BITS_FLAG}"
+  CFLAGS_JDK="${CFLAGS_JDK}${ADDED_CFLAGS}"
+  CXXFLAGS_JDK="${CXXFLAGS_JDK}${ADDED_CXXFLAGS}"
+  LDFLAGS_JDK="${LDFLAGS_JDK}${ADDED_LDFLAGS}"
 ])
 
 AC_DEFUN_ONCE([PLATFORM_SETUP_OPENJDK_TARGET_BITS],