diff --git a/c/tex_parser/Makefile b/c/tex_parser/Makefile
index abb4a39..a665951 100644
--- a/c/tex_parser/Makefile
+++ b/c/tex_parser/Makefile
@@ -29,20 +29,20 @@ ifeq ($(mode),)
 	mode = debug
 endif
 ifeq ($(mode),debug)
-	CFLAGS = -O0 -g -std=gnu99 -pedantic -Wextra -Wconversion
-	LDFLAGS =
+	CFLAGS := -O0 -g -std=gnu99 -pedantic -Wextra -Wconversion $(CFLAGS)
+	LDFLAGS := $(LDFLAGS)
 endif
 ifeq ($(mode),profile)
-	CFLAGS = -O0 -g -p -ftest-coverage -Wcoverage-mismatch
-	LDFLAGS = -g -p
+	CFLAGS := -O0 -g -p -ftest-coverage -Wcoverage-mismatch $(CFLAGS)
+	LDFLAGS := -g -p $(LDFLAGS)
 endif
 ifeq ($(mode),develop)
-	CFLAGS += -O2 -g
-	LDFLAGS += -O1
+	CFLAGS := -O2 -g $(CFLAGS)
+	LDFLAGS := -O1 $(LDFLAGS)
 endif
 ifeq ($(mode),release)
-	CFLAGS += -O2
-	LDFLAGS += -O1
+	CFLAGS := -O2 $(CFLAGS)
+	LDFLAGS := -O1 $(LDFLAGS)
 endif
 
 CFLAGS += -Wall
@@ -74,9 +74,9 @@ change_make_options:
 ifneq ($(mode)|$(CFLAGS)|$(LDFLAGS), $(OLD_BUILD_MODE)|$(OLD_BUILD_CFLAGS)|$(OLD_BUILD_LDFLAGS))
 	@echo CLEANING...
 	@make clean &>/dev/null
-	@echo MODE=$(mode) > make_options.out
-	@echo CFLAGS=$(CFLAGS) >> make_options.out
-	@echo LDFLAGS=$(LDFLAGS) >> make_options.out
+	@echo "MODE=$(mode)" > make_options.out
+	@echo "CFLAGS=$(CFLAGS)" >> make_options.out
+	@echo "LDFLAGS=$(LDFLAGS)" >> make_options.out
 endif
 
 %.o :