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Does Visual Studio not optimize #include guards as-is? Other (better?) compiler do so, and I imagine it is quite easy.

Tom
– Tom

2010-03-04 06:11:49 +00:00
Commented Mar 4, 2010 at 6:11
3

Why do you put the pragma after the ifndef? Is there a benefit?

user1095108
– user1095108

2014-05-13 23:04:11 +00:00
Commented May 13, 2014 at 23:04
3

@user1095108 Some compilers will use the header guards as delimiter to know if the file contain only code that have to be instantiated once. If some code is outside the header guards, then the whole file might be considered maybe instantiable more than once. If that same compiler don't support pragma once, then it will ignore that instruction. Therefore, putting the pragma once inside the header guards is the most generic way to make sure that at least header guards can be "optimized".

Klaim
– Klaim

2014-05-14 10:52:41 +00:00
Commented May 14, 2014 at 10:52

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