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I have tried using the "C++11" premake flag, to get the GNU C++ compiler to do a C++11 compilation.

However, this flag is not recognized and I get the message "invalid flag".

The statement I used in the premake lua script is the following, at either the project or configuration level:

flags {"C++11"}

I am using premake4 on Windows 10 through MSYS. The g++ version is 4.8.1 and supports C++11. (When I use make directly, I am passing the c++11 flag as a compilation option to the compiler and it works.)

How can I proceed to get a C++11 compilation using premake?

SSteven
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2 Answers2

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Well, I have tried a few things and I have a solution. It works.

1) First, with premake4, the flags {"C++11"} statement doesn't appear to work. What I mean is, on premake4, the C++11 flag isn't recognized. Note that the flags statements itself is valid on premake4 but (apparently) not the C++11 flag .

2) On premake5, the flags statement itself has been deprecated. So you can't use flags {"C++11"} on premake5. Instead, use the cppdialect "C++11" statement. I used it within the configuration blocks.

3) Now, you can issue the statement to create the makefiles using premake5. Eg:

premake5 --file=premake-lua-scriptname.lua gmake

4) Later, when you run the generated makefiles, you will find the binary created, by default, in the bin subdirectory subordinate to the dir containing the premake5 lua script. Take my suggestion and override this default to have it created in the same dir as the lua script. (I'll explain why below.) You override this default using the targetdir function, which can be issued at the project level. Eg:

targetdir "."

5) Note that the current (alpha12) release of premake5 doesn't support the clean action. To invoke the clean action, you will have to use premake4. That's why I suggested creating the binary in the default dir. premake4 then cleans it by default.

All this works. However, is there a better solution?

SSteven
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  • I think it is preferred practice to use `gmake2`, as the Makefile format will be a bit more modern that with `gmake`. – alexpanter Feb 01 '21 at 12:59
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For windows build you do not need to specify anything since the vs version implies support of the required standard, so premake5.exe vs2012 or later ver enough.

For linux or macOS use

buildoptions "-std=c++11"

Dmytro Dadyka
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    As @SSteven mentioned, premake5-alpha12+ use `cppdialect "C++11"`. However, C++20 is not supported yet, so in this particular case I had to use `buildoptions "--std=c++20"` (with two hyphens). – hsandt Jun 09 '20 at 17:04
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    Just realized `-std=c++20` is perfectly fine, but you need 2 hyphens when using space `--std c++20` – hsandt Jun 09 '20 at 19:03