diff --git a/xpcom/tests/Makefile.in b/xpcom/tests/Makefile.in

index bb031c9..68a7b8e 100644

--- a/xpcom/tests/Makefile.in

+++ b/xpcom/tests/Makefile.in

@@ -151,6 +151,12 @@

# Make sure we have symbols in case we need to debug these.

MOZ_DEBUG_SYMBOLS = 1

+ifdef SOLARIS_SUNPRO_CXX

+ifeq (sparc,$(findstring sparc,$(OS_TEST)))

+MOZ_OPTIMIZE_FLAGS = -xO3

+endif

+endif

+

include $(topsrcdir)/config/rules.mk

LOCAL_INCLUDES = \