qFatal argument: conversion of QString to const char* results in warning "format string is not a string literal"

Question

Under Qt5.9 and clang++-6.0.0,

QString ret;
qFatal(ret.toLatin1().constData());

yields a warning "format string is not a string literal".

What's wrong, and what is the right way to accomplish the required conversion from QString to a C string?

PS: A closely related question is Converting QString to char*. Here, however, different solutions are possible thanks to the printf-like argument list of qFatal.

Possible duplicate of [Converting QString to char\*](https://stackoverflow.com/questions/5505221/converting-qstring-to-char) — Mohammad Kanan, Mar 18 '18 at 22:38
Edited question to say how it differs from #5505221 (Converting QString to char*) — Joachim W, Mar 19 '18 at 07:18
I recommend you modify the title to indicate that heart of the issue is `qFatal` usage, it will be much more useful reference. — Mohammad Kanan, Mar 19 '18 at 07:21

score 2 · Accepted Answer · answered Mar 18 '18 at 22:29

2

qFatal allows for the variadic ... argument known from printf. Thus

qFatal("%s", ret.toLatin1().constData());

and the warning is gone.

answered Mar 18 '18 at 22:29

Joachim W

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qFatal argument: conversion of QString to const char* results in warning "format string is not a string literal"

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