clang++ 20 fix: Wno-error=unused-command-line-argument

Author: lukeshingles

Makefile

@@ -55,7 +55,7 @@ $(info detected compiler is $(COMPILER_NAME) major version $(COMPILER_VERSION_NU
 CXXFLAGS += -std=c++23 -fstrict-aliasing
 
 ifneq ($(COMPILER_NAME),NVHPC)
-	CXXFLAGS += -ftree-vectorize -Wunused-macros -Werror -Wno-error=unknown-pragmas -Wno-error=cast-function-type -MD -MP -ftrivial-auto-var-init=pattern
+	CXXFLAGS += -ftree-vectorize -Wunused-macros -Werror -Wno-error=unknown-pragmas -Wno-error=cast-function-type -Wno-error=unused-command-line-argument -MD -MP -ftrivial-auto-var-init=pattern
 endif
 
 # CXXFLAGS += -DUSE_SIMPSON_INTEGRATOR=true