Merge pull request #1441 from Platin21/fix/multiple-llvm-versions

Makes it possible to use llvm 12 13 and 11 for building on macOS

Makefile

@@ -8,22 +8,34 @@ CC=clang
 OS=$(shell uname)
 
 ifeq ($(OS), Darwin)
+    
     ARCH=$(shell uname -m)
-    LLVM_CONFIG=llvm-config
+    LLVM_CONFIG=
 
-    # LLVM Version Setting  
-    LLVM_VERSION_PATTERN="^11\."
-    LLVM_VERSION="11"
+    # allow for arm only llvm's with version 13
     ifeq ($(ARCH), arm64)
-	LLVM_VERSION="13"
-        LLVM_VERSION_PATTERN="^13"
-    endif 
+        LLVM_VERSIONS = "13.%.%"
+    else
+    # allow for x86 / amd64 all llvm versions begining from 11
+        LLVM_VERSIONS = "13.%.%" "12.0.1" "11.1.0"
+    endif
 
-    ifneq ($(shell llvm-config --version | grep $(LLVM_VERSION_PATTERN)),)
+    LLVM_VERSION_PATTERN_SEPERATOR = )|(
+    LLVM_VERSION_PATTERNS_ESCAPED_DOT = $(subst .,\.,$(LLVM_VERSIONS))
+    LLVM_VERSION_PATTERNS_REPLACE_PERCENT = $(subst %,.*,$(LLVM_VERSION_PATTERNS_ESCAPED_DOT))
+    LLVM_VERSION_PATTERN_REMOVE_ELEMENTS = $(subst " ",$(LLVM_VERSION_PATTERN_SEPERATOR),$(LLVM_VERSION_PATTERNS_REPLACE_PERCENT))
+    LLMV_VERSION_PATTERN_REMOVE_SINGLE_STR = $(subst ",,$(LLVM_VERSION_PATTERN_REMOVE_ELEMENTS))
+    LLVM_VERSION_PATTERN = "^(($(LLMV_VERSION_PATTERN_REMOVE_SINGLE_STR)))"
+
+    ifneq ($(shell llvm-config --version | grep -E $(LLVM_VERSION_PATTERN)),)
         LLVM_CONFIG=llvm-config
     else
-        $(error "Requirement: llvm-config must be version $(LLVM_VERSION)")
-    endif
+        ifeq ($(ARCH), arm64)
+            $(error "Requirement: llvm-config must be base version 13 for arm64")
+        else 
+            $(error "Requirement: llvm-config must be base version greater than 11 for amd64/x86")
+        endif 
+    endif 
 
     LDFLAGS:=$(LDFLAGS) -liconv
     CFLAGS:=$(CFLAGS) $(shell $(LLVM_CONFIG) --cxxflags --ldflags)