Build fix for Mac OS X.

Makefile

@@ -253,8 +253,8 @@ $(SIMPLE_CXX_TESTS): % : %.cc
 	$(E) CXX $<
 	$(Q) $(CXX) $(CXXFLAGS) $(CPPFLAGS) -o $@ tests/testmain.o $< $(LIBUPB)
 
-VALGRIND=valgrind --leak-check=full --error-exitcode=1 --track-origins=yes
-#VALGRIND=
+#VALGRIND=valgrind --leak-check=full --error-exitcode=1 --track-origins=yes
+VALGRIND=
 test: tests
 	@set -e  # Abort on error.
 	@for test in $(SIMPLE_TESTS) $(SIMPLE_CXX_TESTS); do \

upb/pb/compile_decoder_x64.c

@@ -263,7 +263,7 @@ void upb_pbdecoder_jit(upb_pbdecoderplan *plan) {
   }
 
   char *jit_code = mmap(NULL, jc->plan->jit_size, PROT_READ | PROT_WRITE,
-                        MAP_32BIT | MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);
+                        MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);
   dasm_encode(jc, jit_code);
   mprotect(jit_code, jc->plan->jit_size, PROT_EXEC | PROT_READ);
   upb_reg_jit_gdb(jc);