Got a strange problem. With our modified llvm here,llvm-gcc won't
bootstrap. It fails compiling unwind-dw2.c during translation from
the gcc IR to llvm. It fails with -O0 -emit-llvm so according to
the docs, this is strictly a frontend bug. A run of delta produced
an 18 line testcase with nothing remarkable in it.
However, it bootstraps fine using the official llvm sources. Note
that the llvm-gcc sources used in both builds is identical.
How can this be?
-Dave
On Apr 19, 2007, at 2:37 PM, David Greene wrote:> Got a strange problem. With our modified llvm here,llvm-gcc won't > bootstrap. It fails compiling unwind-dw2.c during translation from > the gcc IR to llvm. It fails with -O0 -emit-llvm so according to > the docs, this is strictly a frontend bug. A run of delta produced > an 18 line testcase with nothing remarkable in it. > > However, it bootstraps fine using the official llvm sources. Note > that the llvm-gcc sources used in both builds is identical.unwind-dw2.c is compiled using newly built llvm-gcc which uses your version of llvm for optimization and code generation. So there may be a bug somewhere in your version of llvm that is mis-compiling llvm-gcc that is used to compile unwind-dw2.c. - Devang> > > How can this be? > > -Dave > _______________________________________________ > LLVM Developers mailing list > LLVMdev at cs.uiuc.edu http://llvm.cs.uiuc.edu > http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Devang Patel wrote:> unwind-dw2.c is compiled using newly built llvm-gcc which uses your > version of llvm for optimization and code generation. So there may be > a bug somewhere in your version of llvm that is mis-compiling llvm-gcc > that is used to compile unwind-dw2.c.Yes, I know the difference is our llvm. But it's not running through the optimizer or machine code generator as I'm compiling with -O0 and - -emit-llvm. In fact the thing never gets beyond gcc-to-llvm translation. I was on to something this afternoon, it looked like an actual gcc frontend bug. It may be that our llvm changes the memory layout just right to expose the problem. I'll take up the investigation tomorrow and see if I can fix it. -Dave -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.6 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFGKD4mgQsI8xjTYs8RAnm7AKCHk0tbuM/QKo934TwCNDKSa7T4GwCcDVhj 4LW26xMl/clqqxDUKm4AByY=HDZG -----END PGP SIGNATURE-----