llvm dev - Jan 2010 - [LLVMdev] make fails to detect changes in case srcdir != objdir

LLVM makefiles can't detect source changes in case objdir != srcdir, e.g.
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 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).

Does anyone know what can be a source for these problems?

	Gregory

On Tuesday 05 January 2010 03:38, Gregory Petrosyan
wrote:
> LLVM makefiles can't detect source changes in case objdir != srcdir,
e.g.
I haven't found that.  I build with objdir != srcdir all the time.
> 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?
> 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.

                                -Dave

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