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Why is this compiling and is there any compiler that can cause the compiler to report this as an error or warning?

I found this example when I ran PCLint in the source code of the project I'm working on. Here is the code snippet:

QString foo()
{
    return false;
}

I compiled the code and verified that it returns an empty string. A real example is a big method in a large class, and somewhere in some remote if branch, this is an isolated

return false;

Well, this is bad coding, a shame for the developer (using SVN / guilt, I could even find out who did it :-)), but seriously, why does the compiler not complain?

My theory is that the compiler translates

return false;

to

return QString(((const char *) false));

However, I do not see all the elementary steps that the compiler takes to do this. First he tries all the QString constructors and finds

QString(const * char);

? , bool const char *. bool , bool, ?

. ( "return false", " "?), (, ), , , ? -Wall g++ .

. , , .

return true;

:

error: conversion from ‘bool’ to non-scalar type ‘QString’ requested

g++ 4.4.3 Ubuntu. , .

+5
1

false . Zero - , NULL- .

, boolean int, int to char* - - .

+7

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