[llvm-dev] BLX relocation regression on Thumb2 bot

[Renato Golin via llvm-dev]

Hi Tim,

You seem to be working around BLX support on ARM, and this linker
error has cropped up on our buildbot:

http://lab.llvm.org:8011/builders/clang-cmake-thumbv7-a15-full-sh/builds/3526

llvm/tools/clang/lib/StaticAnalyzer/Checkers/MallocChecker.cpp:

(.text._ZN5clang4ento24ProgramStatePartialTraitIN4llvm12ImmutableMapIPKNS0_7SymExprEN12_GLOBAL__N_111ReallocPairENS2_16ImutKeyValueInfoIS6_S8_EEEEE13DeleteContextEPv+0x88):

relocation truncated to fit: R_ARM_THM_JUMP24 against symbol `operator
delete(void*)@@GLIBCXX_3.4' defined in .text section in
/usr/lib/gcc/arm-linux-gnueabihf/4.8/libstdc++.so

If I read the AAELF ABI document correctly, that relocation is used
when the linker is building a veneer for under-reaching branches,
which seems to be one of your changes (269101), though that was
supposed to be MachO only.

Do you have any ideas on the issue?

cheers,
-renato

PS: I'm bisecting it right now, but it's self hosted + compiler-rt, so
it will take a while. Also, I fear whatever I find will be just
uncovering the problem, not causing it.