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Hi all.<BR>
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I've got a situation where I'm creating generated source files (from bison/flex, actually, but I'm writing my own rules for it since I need specialized support for C++ output, etc.)<BR>
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However I need to compile the generated output into two different libraries, building two different ways (with different #defines/compiler flags).<BR>
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So I have tried using add_custom_command() with OUTPUT, but the documentation says: <BR>
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"Do not list the output in more than one independent target that may build in parallel or the two instances of the rule may conflict (instead use add_custom_target to drive the command and make the other targets depend on that one)."<BR>
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Sure enough, it seems that if I have my different libraries depend on these outputs I get problems during parallel builds. So then I tried to use add_custom_target(), but that says:<BR>
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"The target has no output file and is ALWAYS CONSIDERED OUT OF DATE"<BR>
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and, sure enough, if I do it this way my source files (and everything that depends on them) rebuild every time I run the build, even if nothing has changed. This is a big bummer.<BR>
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How can I have generated source files compiled different ways into different libraries, but not have them (and anything that depends on them) rebuilt every time?<BR>
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The only way I've thought of so far is to have two different add_custom_command() options with the same input but different output (in different directories maybe), one for each target. This means I need to generate the files twice even though the output source files will have identical content. But as long as I don't have to REBUILD them every time maybe that's not so bad. I haven't tried this yet though. Are there other options?
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