FYI, from the jamming list

From: David Abrahams (dave_at_[hidden])
Date: 2003-11-25 17:09:14

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From: Matt Armstrong <matt_at_[hidden]>
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Subject: [jamming] [BUG] jam 2.5rc3 and parallel builds
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Date: Mon, 24 Nov 2003 09:08:09 -0800
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I've found and isolated a bug with parallel builds (-j<n>) and jam
2.5rc3.

A small source tree that exhibits the bug is at
//guest/matt_armstrong/jam/bug/1/...

A .h file is generated at run time. It gets into the dependency tree
via normal header scanning.

With -j1 builds, the generated.h file is built first and everything is
fine. With -j2 or higher, the generated.h file is built first, but
other .c files that #include it get built in parallel and fail.

I haven't been able to decipher make1[abcd] well enough to figure out
what is going on or develop a fix. I have discovered no workaround
either (e.g. making 'first' depend on generated.h doesn't seem to help).
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Dave Abrahams
Boost Consulting
www.boost-consulting.com
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