How to force compile C source by C++ compiler?

[fsb4000]

I am writing an application in C subset of C ++ and use Qt Creator as an IDE. I would like to know how to make Qt Creator to compile C code with a C ++ compiler.
Thanks in advance for answers!

[raven-worx]

@fsb4000
AFAIK most compilers do that automatically when the file has a .c extension?
Otherwise you would need to specify the corresponding flag for your compiler. Unfortunately this can't be done straight forward using qmake.

[jsulm]

@fsb4000 If you have a C++ compiler then you should have C compiler as well. Which compiler do you have? What file name extension do you use for your source code files (you should use .c for C)?

[fsb4000]

Sorry for bad english, I think I do not accurately express.

1. I am writing an application in C subset of C ++ and use Qt Creator as an IDE.
2. Now it works like this:

gcc -c <some flags> main.o main.c
gcc  -o <app_name> main.o ....

3. I want to test that my code works with C++ compiler. So I can test both C and C++ support. So I want similar to this:

contains(CPP, 1):{
    QMAKE_CC = QMAKE_CXX
    QMAKE_CFLAGS = QMAKE_CXXFLAGS
} else {
    CONFIG += use_c_linker
}

It does not work, but it works like this:

contains(CPP, 1):{
    QMAKE_CC = g++
    QMAKE_CFLAGS = -std=c++14 <other flags>
} else {
    CONFIG += use_c_linker
}

But I want this to work at least with these three compilers: g++, clang, MSVC, not only g++.

[JohanSolo]

@fsb4000 said in How to force compile C source by C++ compiler?:

But I want this to work at least with these three compilers: g++, clang, MSVC, not only g++.

IIRC MSVC does not have any more a pure C compiler.

[fsb4000]

I figured out.
Solution::

contains(CPP, 1):{
    QMAKE_CC = $$QMAKE_CXX
    QMAKE_CFLAGS  = $$QMAKE_CXXFLAGS
} else {
    CONFIG += use_c_linker
}

Thank you all for for your time!