SDL_assert: warning C4127

SDL Development
1

Hello,

I’m compiling SDL2 app with msvc 2012 with /W4 setting.
When using SDL_assert* macros, msvc is complaining:

warning C4127: conditional expression is constant

I’ve solved this by changing the condition, see the attached patch.–
Matej
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2

#define bla(x) do { … } while(0);
is a common idiom (which is supposed to be constant), seems stupid of
the compiler to complain about that.
That your compiler gives a warning about while(0) being constant but not
about while(-1 == LINE) being constant (even though it is just as
constant), is inconsistent and likely to “break” with later versions of
the compiler or other compilers.

Cheers,
DanielAm 06.09.2013 21:42, schrieb Matej ?vec:

Hello,

I’m compiling SDL2 app with msvc 2012 with /W4 setting.
When using SDL_assert* macros, msvc is complaining:

warning C4127: conditional expression is constant

I’ve solved this by changing the condition, see the attached patch.

3

How about some _pragma magic to keep the VS compiler from complaining?

See here:
c++ - How to disable C4127 for do {} while(false) - Stack Overflow 9/6/2013 12:42 PM, Matej ?vec wrote:

Hello,

I’m compiling SDL2 app with msvc 2012 with /W4 setting.
When using SDL_assert* macros, msvc is complaining:

warning C4127: conditional expression is constant

I’ve solved this by changing the condition, see the attached patch.

–
Matej

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4

I’ve solved this by changing the condition, see the attached patch.

It’s a clever idea. I’ve just put something like this in revision control.

–ryan.