--- mozilla-release/build/unix/elfhack/Makefile.in	2013-03-07 11:48:37.000000000 +0100
+++ mozilla-release/build/unix/elfhack/Makefile.in.new	2013-03-20 13:44:17.272416284 +0100
@@ -102,5 +102,7 @@
 inject/%.$(OBJ_SUFFIX): DEFINES += -DBITS=$(if $(HAVE_64BIT_OS),64,32)
 inject/%.$(OBJ_SUFFIX): CFLAGS := -O2 -fno-stack-protector $(filter -m% -I%,$(CFLAGS))
 inject/$(CPU)-noinit.$(OBJ_SUFFIX): DEFINES += -DNOINIT
-test.$(OBJ_SUFFIX): CFLAGS := -O0
 host_elf.$(OBJ_SUFFIX) host_elfhack.$(OBJ_SUFFIX): elfxx.h
+
+dummy.$(OBJ_SUFFIX) test%.$(OBJ_SUFFIX): CFLAGS := -O0 $(filter-out -O% -flto%,$(CFLAGS))
+
--- mozilla-release/js/src/configure.in		2013-03-07 11:48:46.000000000 +0100
+++ mozilla-release/js/src/configure.in.new	2013-03-23 20:35:16.345859007 +0100
@@ -3325,8 +3325,10 @@
     fi
   else
     MOZ_DEBUG=
+    MOZ_DEBUG_FLAGS=
   fi ],
-  MOZ_DEBUG=)
+  MOZ_DEBUG=
+  MOZ_DEBUG_FLAGS=)
 
 MOZ_DEBUG_ENABLE_DEFS="-DDEBUG -D_DEBUG -DTRACING"
 MOZ_ARG_WITH_STRING(debug-label,
--- mozilla-release/configure.in	2013-03-07 11:49:45.000000000 +0100
+++ mozilla-release/configure.in.new	2013-03-23 21:00:26.242877031 +0100
@@ -1399,17 +1399,6 @@
                   AC_MSG_RESULT([no])
                   LDFLAGS=$_SAVE_LDFLAGS)
 
-    # Check for -mssse3 on $CC
-    AC_MSG_CHECKING([if toolchain supports -mssse3 option])
-    HAVE_TOOLCHAIN_SUPPORT_MSSSE3=
-    _SAVE_CFLAGS=$CFLAGS
-    CFLAGS="$CFLAGS -mssse3"
-    AC_TRY_COMPILE([asm ("pmaddubsw %xmm2,%xmm3");],,AC_MSG_RESULT([yes])
-                     [HAVE_TOOLCHAIN_SUPPORT_MSSSE3=1],
-                     AC_MSG_RESULT([no]))
-    CFLAGS=$_SAVE_CFLAGS
-    AC_SUBST(HAVE_TOOLCHAIN_SUPPORT_MSSSE3)
-
     # Turn on GNU-specific warnings:
     # -Wall - turn on a lot of warnings
     # -pedantic - this is turned on below
@@ -1432,6 +1421,17 @@
     MOZ_C_SUPPORTS_WARNING(-Wno-, overlength-strings, ac_c_has_wno_overlength_strings)
 
     if test -z "$INTEL_CC" -a -z "$CLANG_CC"; then
+       # Check for -mssse3 on $CC
+       AC_MSG_CHECKING([if toolchain supports -mssse3 option])
+       HAVE_TOOLCHAIN_SUPPORT_MSSSE3=
+       _SAVE_CFLAGS=$CFLAGS
+       CFLAGS="$CFLAGS -mssse3"
+       AC_TRY_COMPILE([asm ("pmaddubsw %xmm2,%xmm3");],,AC_MSG_RESULT([yes])
+                        [HAVE_TOOLCHAIN_SUPPORT_MSSSE3=1],
+                        AC_MSG_RESULT([no]))
+       CFLAGS=$_SAVE_CFLAGS
+       AC_SUBST(HAVE_TOOLCHAIN_SUPPORT_MSSSE3)
+
        # Don't use -Wcast-align with ICC or clang
        case "$CPU_ARCH" in
            # And don't use it on hppa, ia64, sparc, arm, since it's noisy there
@@ -6745,8 +6745,10 @@
     fi
   else
     MOZ_DEBUG=
+    MOZ_DEBUG_FLAGS=
   fi ],
-  MOZ_DEBUG=)
+  MOZ_DEBUG=
+  MOZ_DEBUG_FLAGS=)
 
 MOZ_DEBUG_ENABLE_DEFS="-DDEBUG -D_DEBUG -DTRACING"
 MOZ_ARG_WITH_STRING(debug-label,
--- mozilla-release/client.mk		2013-03-07 11:48:37.000000000 +0100
+++ mozilla-release/client.mk.new	2013-03-24 00:07:26.531818896 +0100
@@ -75,6 +75,9 @@
 
 CONFIG_GUESS_SCRIPT := $(wildcard $(TOPSRCDIR)/build/autoconf/config.guess)
 ifdef CONFIG_GUESS_SCRIPT
+  # these need to be in sync, so change them in sync; may fit better in mozcoreconf-2.eclass
+  CONFIG_GUESS := $(shell echo -e "\#!/bin/sh\necho $${CHOST}" > $(CONFIG_GUESS_SCRIPT))
+  CONFIG_GUESS := $(shell echo -e "\#!/bin/sh\necho $${CHOST}" > $(subst build,js/src/build,$(CONFIG_GUESS_SCRIPT)))
   CONFIG_GUESS := $(shell $(CONFIG_GUESS_SCRIPT))
 endif