--- a/src/libnnp/makefile
+++ b/src/libnnp/makefile
@@ -72,11 +72,11 @@ headers: version
 
 version:
 	@$(eval GIT_VERSION = $(shell git describe --tags --always))
-	@sed -i.bak -E "s/(NNP_GIT_VERSION) .*/\1 \"$(GIT_VERSION)\"/" version.h
+	@sed -i.bak -E "s|(NNP_GIT_VERSION) .*|\1 \"$(GIT_VERSION)\"|" version.h
 	@$(eval GIT_REV = $(shell git rev-parse HEAD))
-	@sed -i.bak -E "s/(NNP_GIT_REV) .*/\1 \"$(GIT_REV)\"/" version.h
+	@sed -i.bak -E "s|(NNP_GIT_REV) .*|\1 \"$(GIT_REV)\"|" version.h
 	@$(eval GIT_BRANCH = $(shell git rev-parse --abbrev-ref HEAD))
-	@sed -i.bak -E "s/(NNP_GIT_BRANCH) .*/\1 \"$(GIT_BRANCH)\"/" version.h
+	@sed -i.bak -E "s|(NNP_GIT_BRANCH) .*|\1 \"$(GIT_BRANCH)\"|" version.h
 	@rm version.h.bak
 
 $(LIB).so: CFLAGS+= -fPIC
@@ -97,9 +97,9 @@ clean: clean-version clean-headers
 	$(RM) $(PROJECT_LIB)/$(LIB).so $(PROJECT_LIB)/$(LIB).a
 
 clean-version:
-	@sed -i.bak -E "s/(NNP_GIT_VERSION) .*/\1 \"\"/" version.h
-	@sed -i.bak -E "s/(NNP_GIT_REV) .*/\1 \"\"/" version.h
-	@sed -i.bak -E "s/(NNP_GIT_BRANCH) .*/\1 \"\"/" version.h
+	@sed -i.bak -E "s|(NNP_GIT_VERSION) .*|\1 \"\"|" version.h
+	@sed -i.bak -E "s|(NNP_GIT_REV) .*|\1 \"\"|" version.h
+	@sed -i.bak -E "s|(NNP_GIT_BRANCH) .*|\1 \"\"|" version.h
 	@rm version.h.bak
 
 clean-headers: