#warning in Visual Studio

Question

In gcc I can do compile-time warnings like this:

#if !defined(_SOME_FEATURE_)
   #warning _SOME_FEATURE_ not defined-- be careful!
#endif

But in Visual Studio this doesn't work. Is there an alternative syntax for #warning?

score 17 · Accepted Answer · answered Apr 21 '10 at 18:48

17

About the closest equivalent would be #pragma message, or possibly #error (the latter stops compilation, the former just prints out the specified error message).

answered Apr 21 '10 at 18:48

Jerry Coffin

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`#pragma message` is not compatible with gcc though. See https://stackoverflow.com/questions/471935/user-warnings-on-msvc-and-gcc – Pierre.Sassoulas Aug 29 '17 at 07:32

score 14 · Answer 2 · answered Apr 21 '10 at 18:49

14

Use #pragma message("Some message")

answered Apr 21 '10 at 18:49

Jasper Bekkers

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Danny Parker · Answer 3 · 2018-06-19T10:10:45.777

8

There is a good article here on how to achieve a similar effect to #warning in visual studio:

http://goodliffe.blogspot.co.uk/2009/07/c-how-to-say-warning-to-visual-studio-c.html

Edit: Here is the relevant section from the above link, however I do recommend reading the article.

#define STRINGIZE_HELPER(x) #x
#define STRINGIZE(x) STRINGIZE_HELPER(x)
#define WARNING(desc) message(__FILE__ "(" STRINGIZE(__LINE__) ") : Warning: " #desc)

// usage:
#pragma WARNING(FIXME: Code removed because...)

edited Jun 19 '18 at 10:10

answered Jun 28 '12 at 12:36

Danny Parker

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The question is for Visual Studio, and at 8 years old was for MSVC. – Danny Parker Nov 19 '18 at 12:02
I thought it had been supposed to be cross-platform. I was wrong. You did not say so. – Yongwei Wu Nov 19 '18 at 15:05

score 0 · Answer 4 · answered Apr 21 '10 at 18:39

0

#pragma WEIRD_VALUES_HERE

is the way I've always seen it done. M$ probably has the pragmas on their site somewhere.

answered Apr 21 '10 at 18:39

Michael Dorgan

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VS `#pragma` Reference: http://msdn.microsoft.com/en-us/library/d9x1s805%28v=VS.80%29.aspx – Nick T Apr 21 '10 at 18:46

score 0 · Answer 5 · answered Apr 21 '10 at 19:00

0

Another thought is template style compile time asserts. Boost has a whole selection of these if you are wanting to check compile time code errors.

answered Apr 21 '10 at 19:00

Michael Dorgan

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The question asks for *warnings*. – Georg Fritzsche Apr 21 '10 at 19:03

#warning in Visual Studio

5 Answers5