diff --git a/win32_functional_tests/Makefile b/win32_functional_tests/Makefile
index 49450126ba..89b611ccae 100644
--- a/win32_functional_tests/Makefile
+++ b/win32_functional_tests/Makefile
@@ -5,7 +5,15 @@
 
 # Compiler options here.
 ifeq ($(USE_OPT),)
-  USE_OPT = -O2 -ggdb
+# this config if debugging is needed, but the binary is about 50M
+# USE_OPT = -c -Wall -O0 -ggdb -g3 -Werror-implicit-function-declaration -Werror -Wno-error=pointer-sign -Wno-error=unused-function -Wno-error=unused-variable -Wno-error=sign-compare -Wno-error=unused-parameter -Wno-error=missing-field-initializers -Wno-error=write-strings
+# this config producec a smaller binary file
+  USE_OPT = -c -Wall -O2           -Werror-implicit-function-declaration  -Wno-error=pointer-sign -Wno-error=unused-function -Wno-error=unused-variable -Wno-error=sign-compare -Wno-error=unused-parameter -Wno-error=missing-field-initializers -Wno-error=write-strings -Wno-error=strict-aliasing
+
+	ifeq ($(OS),Windows_NT)
+	else
+ 	 USE_OPT +=  -m32
+	endif
 endif
 
 # C specific options here (added to USE_OPT).