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From: "ppalka at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug c++/96780] debuginfo for std::move and std::forward isn't useful
Date: Wed, 09 Mar 2022 15:34:28 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D96780

--- Comment #12 from Patrick Palka <ppalka at gcc dot gnu.org> ---
I should mention I noticed a significant reduction in compile time, memory
usage and unstripped object file size in some cases with the proposed patch=
 at
https://gcc.gnu.org/pipermail/gcc-patches/2022-March/591091.html.

For instance, for the range-v3 test file
test/algorithm/set_symmetric_difference4.cpp compiled with -O2 -g and a
non-checking compiler, compile time/GC allocations/object file size decreas=
es
from
  8.29s/551M/3508K
to
  8.00s/541M/3104K.

The object file size decrease (naively measured with du) here is particular=
ly
surprising, nearly a 12% decrease.  I suppose this means debug info for inl=
ined
calls to std::move/forward accounts for >=3D12% of the debug info size, whi=
ch we
no longer emit with the patch.=