on MacOS llvm is not installed by default, add a test for that. Before this fix
the make run proceeded, producing meaningless error messages.
MODIFY
llvm_mode/Makefile
llvm_mode/Makefile
@@ -43,8 +43,12 @@ LLVM_BINDIR = $(shell $(LLVM_CONFIG) --bindir 2>/dev/null)
LLVM_STDCXX = gnu++11
LLVM_APPLE = $(shell clang -v 2>&1 | grep -iq apple && echo 1 || echo 0)
+ifeq "$(LLVMVER)" ""
+ $(error llvm_mode needs llvm-config, which was not found)
+endif
+
ifeq "$(LLVM_UNSUPPORTED)" "1"
- $(warn llvm_mode only supports versions 3.8.0 up to 9)
+ $(warn llvm_mode only supports llvm versions 3.8.0 up to 9)
endif
ifeq "$(LLVM_MAJOR)" "9"

on MacOS llvm is not installed by default, add a test for that. Before this fix
the make run proceeded, producing meaningless error messages.