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c++cemacsmakefileflymake

Setup makefile to check both c and c++ source files with emacs flymake

I am trying to set up syntax checking with flymake and I've got the basic setup working.

My makefile for flymake is simply like follows: 

INCLUDES = -I ./inc ## list of more includes omitted for brevity
.PHONY: check-syntax
check-syntax:
    gcc -Wall -Wextra -pedantic -fsyntax-only -Wno-variadic-macros -std=c99 $(INCLUDES) $(CHK_SOURCES)

This works ok for my C sources.

Now how to use the same makefile and the same check-syntax target for C++? I can't set multiple -std options like -std=c99 -std=c++98 to the same gcc invocation or can I? Do I need to use some conditional? I can't have multiple check-syntax targets on the same Makefile.

Solution

  • You could split it up into two targets:

    check-syntax: check-syntax-c check-syntax-cxx

    Then check the syntax using the C compiler and the C flags in one target, and using the C++ and C++ flags for the other.

    Although you have to split up your sources in C and C++ sources, which you should do anyway.

    If you don't have the files split already, you can do it using a GNU Make text function named filter to split the sources:

    CHK_SOURCES_C   = $(filter %.c,$(CHK_SOURCES))
CHK_SOURCES_CXX = $(filter %.cpp,$(CHK_SOURCES))