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On Wed, 2 Jun 2010 03:16:12 -0400 |
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Mike Frysinger <vapier@g.o> wrote: |
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> On Monday, May 31, 2010 15:12:46 Michał Górny wrote: |
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> > There are many simple applications which come without neither a |
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> > sophisticated build system or even a tiny Makefile. In some cases, |
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> > such applications aren't even packages as tarball -- a single, |
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> > compressed source file is published instead. |
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> > |
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> > In case of these applications, ebuilds inherit |
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> > toolchain-funcs.eclass to retrieve compiler information |
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> > (tc-getCC/tc-getCXX) and call compiler manually, passing |
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> > appropriate flags. |
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> |
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> use emake then and leverage make's implicit rules. |
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The implicit make rules are less universal and -- in the fact -- pretty |
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poor. They're strictly make-dependant, which reduces the amount of |
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control over their behavior. In my opinion, if we should ever use such |
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behavior, it should be rather technical implementation of the functions |
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I'm proposing instead of inline use. |
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POSIX (man 1p make) defines only simple rule for C files: |
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$(CC) $(CFLAGS) $(LDFLAGS) -o $@ $< |
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I wasn't able to find a rule for C++ files. GNU Make seems a little |
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better but it's documentation is blurry. Although it supports both C |
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and C++, and pretty wide set of variables, it's still less than |
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solution proposed by me. And it's only 'de-facto standard', which isn't |
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guaranteed to be kept unchanged in the future. |
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Namely, advantages of my solution over directly calling emake is: |
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1) direct control over how compiler will be called == better |
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portability, |
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2) possibility of using any output filename (with emake we'd have to |
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rename), |
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3) possibility of clearly using multiple input files, |
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4) possibility of using any input file suffix, |
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5) clear separation between user-specified and ebuild-specified flags |
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(yes, I'm aware of '+=' GNU make extension). |
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And after all, starting a make jobserver for a single compiler process |
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doesn't seem really useful. |
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> sys-apps/unscd is a pretty straight forward example. |
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In my opinion it's rather a poor example. It's the simplest case |
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possible -- single file, no additional flags, no libs. |
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-- |
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Best regards, |
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Michał Górny |
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|
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<http://mgorny.alt.pl> |
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<xmpp:mgorny@××××××.ru> |
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