Warning C4715 with usage of MSVC 2019 Compiler

[Markus_Metrohm]

Hello all,

By compiling my Windows Desktop Application with the MSVC 2019 Compiler (16.9.32126.311 amd64) I get the warning C4715. A look into the Qt Code in file qlogging.h shows the following lines:

#ifndef Q_CC_MSVC
    Q_NORETURN
#endif
    Q_DECL_COLD_FUNCTION
    void fatal(const char *msg, ...) const noexcept Q_ATTRIBUTE_FORMAT_PRINTF(2, 3);

In my Setup, the Q_CC_MSVC define is set. This makes sense, but I don't understand why Q_NORETURN is not used in this case. After changing the lines to

    Q_NORETURN
    Q_DECL_COLD_FUNCTION
    void fatal(const char *msg, ...) const noexcept Q_ATTRIBUTE_FORMAT_PRINTF(2, 3);

the warning disappears. In the Microsoft Docs you find the confirmation that the MSVC Compiler knows the attribute __declspec(noreturn).

Could someone tell me, why this check is done this way? Have I to change my configuration? Is there a further define that has to be set?

Thanks for supporting me.

Regards Markus

[Christian Ehrlicher]

What Qt version?

[Markus_Metrohm]

I'm working with 5.15.8. Sorry for this missing info.

[Christian Ehrlicher]

You should take what Q_NORETURN is defined to in your case and also ask the commercial Qt support - 5.15.8 is not publicity available so no real help from our side possible.