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Don't omit dynamic relocations for the GOT.

Description

Don't omit dynamic relocations for the GOT.

Where Clang's AArch64 backend seems to differ from the X86 backend is
that it tends to use the GOT more aggressively.

After getting CloudABI PIEs working on x86-64, I noticed that accessing
global variables would still crash on aarch64. Tracing it down, it turns
out that the GOT was filled with entries assuming the base address was
zero.

It turns out that we skip generating relocations for GOT entries in case
the relocation pointing towards the GOT is relative. Whether the thing
pointing to the GOT is absolute or relative shouldn't make any
difference; the GOT entry itself should contain the absolute address,
thus needs a relocation regardless.

Approved by: rafael
Differential Revision: http://reviews.llvm.org/D18739

Details

Committed
edApr 5 2016, 1:17 PM
Differential Revision
D18739: Don't omit dynamic relocations for the GOT.
Parents
rL265452: llvm-dwp: Handle dwo files produced by GCC
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