Add llvm-config version 11 check for Darwin in Makefile

Makefile

@@ -8,26 +8,31 @@ CC=clang
 OS=$(shell uname)
 
 ifeq ($(OS), Darwin)
-    LLVM_CONFIG=llvm-config
-
-    LDFLAGS:=$(LDFLAGS) -liconv
-    CFLAGS:=$(CFLAGS) $(shell $(LLVM_CONFIG) --cxxflags --ldflags)
-    LDFLAGS:=$(LDFLAGS) -lLLVM-C
+	LLVM_CONFIG=llvm-config
+	ifneq ($(shell llvm-config --version | grep '^11\.'),)
+		LLVM_CONFIG=llvm-config
+	else
+		$(error "Requirement: llvm-config must be version 11")
+	endif
+
+	LDFLAGS:=$(LDFLAGS) -liconv
+	CFLAGS:=$(CFLAGS) $(shell $(LLVM_CONFIG) --cxxflags --ldflags)
+	LDFLAGS:=$(LDFLAGS) -lLLVM-C
 endif
 ifeq ($(OS), Linux)
-    LLVM_CONFIG=llvm-config-11
-    ifneq ($(shell which llvm-config-11 2>/dev/null),)
-        LLVM_CONFIG=llvm-config-11
-    else
-            ifneq ($(shell llvm-config --version | grep '^11\.'),)
-                    LLVM_CONFIG=llvm-config
-            else
-                    $(error "Requirement: llvm-config must be version 11")
-            endif
-    endif
-
-    CFLAGS:=$(CFLAGS) $(shell $(LLVM_CONFIG) --cxxflags --ldflags)
-    LDFLAGS:=$(LDFLAGS) $(shell $(LLVM_CONFIG) --libs core native --system-libs)
+	LLVM_CONFIG=llvm-config-11
+	ifneq ($(shell which llvm-config-11 2>/dev/null),)
+		LLVM_CONFIG=llvm-config-11
+	else
+		ifneq ($(shell llvm-config --version | grep '^11\.'),)
+			LLVM_CONFIG=llvm-config
+		else
+			$(error "Requirement: llvm-config must be version 11")
+		endif
+	endif
+
+	CFLAGS:=$(CFLAGS) $(shell $(LLVM_CONFIG) --cxxflags --ldflags)
+	LDFLAGS:=$(LDFLAGS) $(shell $(LLVM_CONFIG) --libs core native --system-libs)
 endif
 
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