[PowerPC] undef Relocation names in PowerPC*.def
glibc's PowerPC /usr/include/asm/sigcontext.h, has this:
#ifdef __powerpc64__
#include <asm/elf.h>
#endif
and that contains defines of all of the relocation symbols, like this:
#define R_PPC_NONE 0
and if that file is included prior to including
include/llvm/Support/ELFRelocs/PowerPC*.def, which we cannot in general
prevent, the result will fail.
As it turns out, this happens when compiling
lld/unittests/DriverTests/GnuLdDriverTest.cpp under PPC64/Linux, because:
lld/include/lld/ReaderWriter/ELFLinkingContext.h includes
lld/unittests/DriverTests/DriverTest.h which includes
utils/unittest/googletest/include/gtest/gtest.h which includes
utils/unittest/googletest/include/gtest/internal/gtest-internal.h which includes
/usr/include/sys/wait.h which includes
/usr/include/signal.h which includes
/usr/include/bits/sigcontext.h which includes
/usr/include/asm/sigcontext.h which includes
/usr/include/asm/elf.h
the test could be fixed to include ReaderWriter/ELFLinkingContext.h before
including unittests/DriverTests/DriverTest.h, but dealing with this in the
*.def files is a more-general solution that localizes the fix to the headers
instead of requiring changes to an unbounded number of other source files (both
in-tree and external).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@248957
91177308-0d34-0410-b5e6-
96231b3b80d8