[LLVMdev] make fails to detect changes in case srcdir != objdir

[Gregory Petrosyan]

On Tue, Jan 05, 2010 at 11:30:41AM -0600, David Greene wrote:
> > I've managed to get my pass listed in 'opt -help' only after removing opt
> > subdir from objdir and running make again. Re-configuring LLVM also does
> 
> It sounds like the dependencies for your pass are not correct.  Where
> did you put it in the LLVM tree and how did you change the Makefiles?

One new .cpp file in lib/Transforms/IPO + RegisterPass<> + mention pass in
LinkAllPasses.h; no changes in makefiles.

> > not trigger rebuild when running make, e.g. after initial 'configure
> > --enable-targets=x86' I've managed to get C backend only after removing
> > objdir and re-configuring (was too lazy to check if 'make clean' is
> > sufficient).
> 
> A non-build after reconfigure is not really a problem.  If nothing in
> the configuration has changed configure is smart enough not to update
> anything so make doesn't see any changes.

Yes, but in my case support for new targets should be built in.

It is entirely possible that I've screwed something up, although I've tried to
follow LLVM docs as closely as possible. LLVM build system is really not the
nicest part of LLVM :-)

	Gregory