Work around Clang < 3.7 integrated assembler bug PC-relative relocs

The qversiontagging.h inline assembly expands to:

  .long qt_version_tag@GOTPCREL

Which, with GCC, Clang >= 3.7 and with the option -no-integrated-as in
previous versions, produces the proper relocation (a R_X86_64_GOTPCREL).
With Clang < 3.7, it instead produces a R_X86_64_32, which is unsuitable
for use in shared libraries: 32-bit displacement is insufficiently wide
and would produce linker errors like

 obj/qftp.o: requires dynamic R_X86_64_32 reloc against 'qt_version_tag' which may overflow at runtime; recompile with -fPIC

Instead, force a 64-bit relocation (an R_X86_64_GOT64), which like the
32-bit version is simply an offset into the GOT of where the address of
the symbol is stored.

Task-number: QTBUG-50749
Change-Id: I7a9e11d7b64a4cc78e24ffff142e039c172b802c
Reviewed-by: Simon Hausmann <simon.hausmann@theqtcompany.com>

0 files changed, 0 insertions, 0 deletions