chore: configure compilers via make

compiler/Makefile

@@ -2,6 +2,8 @@ BUILD_DIR=./build
 Python3_EXECUTABLE=
 BINDINGS_PYTHON_ENABLED=ON
 PARALLEL_EXECUTION_ENABLED=OFF
+CC_COMPILER=
+CXX_COMPILER=
 
 export PATH := $(BUILD_DIR)/bin:$(PATH)
 
@@ -17,9 +19,23 @@ else
         CMAKE_CCACHE_OPTIONS=
 endif
 
+ifneq ($(CC_COMPILER),)
+		CC_COMPILER_OPTION=-DCMAKE_C_COMPILER=$(CC_COMPILER)
+else
+		CC_COMPILER_OPTION=
+endif
+
+ifneq ($(CXX_COMPILER),)
+		CXX_COMPILER_OPTION=-DCMAKE_CXX_COMPILER=$(CXX_COMPILER)
+else
+		CXX_COMPILER_OPTION=
+endif
+
 $(BUILD_DIR)/configured.stamp:
 	cmake -B $(BUILD_DIR) -GNinja ../llvm-project/llvm/ \
 	$(CMAKE_CCACHE_OPTIONS) \
+	$(CC_COMPILER_OPTION) \
+	$(CXX_COMPILER_OPTION) \
 	-DLLVM_ENABLE_PROJECTS=mlir \
 	-DLLVM_BUILD_EXAMPLES=OFF \
 	-DLLVM_TARGETS_TO_BUILD="host" \