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Re: Precompiled header problem

On Apr 25, 2006, at 12:17 PM, Chris Espinosa wrote:
Well, there's a very simple explanation. const definitions are code, and gcc stops precompiling headers when it reaches the first line of code.

Precompiled headers are applied as a prefix to every source file in your target. So if gcc emitted code for these const definitions in the pch, you'd have multiple definitions of the constants, one for every source file. The linker wouldn't like that.

You have two choices:

1) Use macros instead of const declarations.
2) Declare the consts as "extern" in your precompiled header, and do the formal definitions in a single source file in your build (not in a header file or the prefix file).

So why would this header work when included in a PCH for some projects, but not this one? If I'm understanding your description of gcc precompilation, I'd expect it to fail wherever it's used in that way. I don't find that to be the case.
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References: 
 >Precompiled header problem (From: "Jeff Schmidt" <email@hidden>)
 >Re: Precompiled header problem (From: Chris Espinosa <email@hidden>)



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