Add a very simple test for the pre-processor.

Validate desired test cases by ensuring the output of glcpp matches
the output of the gcc preprocessor, (ignoring any lines of the gcc
output beginning with '#').

Only one test case so far with a trivial #define.

1 files changed, 4 insertions, 0 deletions

diff --git a/Makefile b/Makefile
index d37e9233ec..38cc1f314a 100644
--- a/Makefile
+++ b/Makefile
@@ -10,5 +10,9 @@ glcpp: glcpp.o glcpp-lex.o glcpp-parse.o hash_table.o
 
 glcpp-lex.c: glcpp-parse.h
 
+test:
+	@(cd tests; ./glcpp-test)
+
 clean:
 	rm -f glcpp-lex.c glcpp-parse.c *.o *~
+	rm -f tests/*.out tests/*.gcc tests/*.expected