[PATCH][GOLD] Avoid generating unused dynamic relocation for __exidx_{start,end}

[Doug Kwan (éæå) <dougkwan at google dot com>]

[resend a previously sent e-mail to include binutils]

Hi Ian,

  This patch fixes a problem in which unnecessary dynamic relocations
are generated for __exidx_{start,end}.  These symbols are special and
references to them should use the local definition.  Currently we
define these symbols in the ARM backend too late.  The patch adds a
new target hook to generate target-specific symbols.


2012-03-13  Doug Kwan  <dougkwan@google.com>

       * arm.cc (Target_arm::do_define_standard_symbols): New method.
       (Target_arm::do_finalize_sections): Remove code which defines
       __exidx_start and __exidx_end.  Make symbol table parameter
       anonymous as it is not used.
       * gold.cc (queue_middle_tasks): Call target hook to define any
       target-specific symbols.
       * target.h (Target::define_standard_symbols): New method.
       (Target::do_define_standard_symbols): Same.
       * testsuite/Makefile.am (arm_exidx_test): Dump relocations also.
       * testsuite/Makefile.in: Regenerate.
       * testsuite/arm_exidx.s: Generate data relocations for __exidx_start
       and __exidx_end.
       * testsuite/arm_exidx_test.sh: Check that no unused dynamic
       relocations are generated for __exidx_start and __exidx_end.



-Doug

Attachment: patch.txt
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