CMake变量的作用域

You need to use set instead of list to affect the variable in the parent scope.

So replace your list command with:

set(source_list ${source_list} ${file_path} PARENT_SCOPE)

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edited Oct 1 '18 at 11:00

Tsyvarev

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answered Apr 5 '12 at 16:25

Fraser

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  It's not global though, siblings will not see. – 0xbaadf00d Apr 4 '17 at 6:32
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  @JoachimW: Why incorporate two answers into the single one? You seems to misunderstand Question/Answer model on Stack Overflow. We do NOT tend to have all solutions in the single accepted answer. Instead, having one answer per solution is perfect. And an answer's quality is primarily measured by the voting, good answers needn't to be marked with the green accept mark. Please, revert this answers merging. – Tsyvarev Oct 1 '18 at 10:37 

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16

PARENT_SCOPE is only for parent, it won't work if you have other non-parent script that want to see it as well.

You need cache for the true "global-like" variable. In your case, use:

SET(source_list  "${source_list}" CACHE INTERNAL "source_list")

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edited Jun 14 '16 at 5:37

answered Aug 5 '14 at 3:05

Ding-Yi Chen

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  It doesn't work for second run of cmake, because value is already in cache. You must clean before build. – Maxim Suslov Feb 25 '16 at 7:23
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  INTERNAL implied FORCE, which means: Use the FORCE option to overwrite existing entries. – Ding-Yi Chen Feb 25 '16 at 22:49 

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8

Another approach is to use global properties. Once you set it:

set_property(GLOBAL PROPERTY source_list_property "${source_list}")

you can read it from everywhere:

get_property(source_list GLOBAL PROPERTY source_list_property)

I used in examples above the different names for property (source_list_property) and for variable (source_list). Maybe it is better to use the same name. But point is to use a property as global variables, and not about naming.

Such global properties aren't in cache.