--- a/src/acinclude.m4
+++ b/src/acinclude.m4
@@ -107,7 +107,7 @@ int main (int argc, char *argv[])
   with_zlib=yes,
   with_zlib=no,
   [AC_MSG_RESULT(cross-compiling)
-  with_zlib=""
+  with_zlib="cross"
   AC_MSG_WARN(Assuming zlib is available)])
 
 if test x$with_zlib != x; then
@@ -116,7 +116,7 @@ fi
 if test x$with_zlib = xyes; then
   ZLIB_VERSION=$(<conf.zlibtest)
   ifelse([$2], , :, [$2])
-else
+elif test x$with_zlib != xcross; then
   ZLIB_CFLAGS=""
   ZLIB_LIBS=""
   ZLIB_VERSION=""
--- a/src/Makefile.in
+++ b/src/Makefile.in
@@ -103,8 +103,10 @@ main: makefile.dep $(Z_OBJS)
 	@ZC@ -o @ZSNESEXE@ $(Z_OBJS) @ZCFLAGS@ @LDFLAGS@
 	rm -f version.o
 
+BUILD_CXX ?= g++
+BUILD_CXXFLAGS ?= -O2 -pipe
 $(PSR): parsegen.cpp
-	@CXX@ @CXXFLAGS@ -o $@ $< -lz
+	$(BUILD_CXX) $(BUILD_CXXFLAGS) -o $@ $< -lz
 
 TOOLSEXE=$(TOOL_D)/archopt $(TOOL_D)/cutrtype $(TOOL_D)/extraext\
 	$(TOOL_D)/macroll $(TOOL_D)/minwhite $(TOOL_D)/nreplace\