[PATCH] PR libstdc++/90634 reduce allocations in filesystem::path construction

[Jonathan Wakely]

On 28/05/19 17:10 +0100, Jonathan Wakely wrote:
>	PR libstdc++/90634
>	* src/filesystem/path.cc (path::_M_split_cmpts()): Fix check for "/".
>	* testsuite/27_io/filesystem/path/construct/90634.cc: New test.
>	* testsuite/experimental/filesystem/path/construct/90634.cc: New test.
>
>	PR libstdc++/90634
>	* include/bits/fs_path.h (path::path(path&&)): Only call
>	_M_split_cmpts() for a path with multiple components.
>	(path::_S_is_dir_sep()): Add missing 'static' keyword to function.
>	* include/experimental/bits/fs_path.h: Likewise.
>	* src/filesystem/path.cc (path::_M_split_cmpts()): Count number of
>	components and reserve space in vector. Return early when there is
>	only one component.
>	* src/filesystem/std-path.cc (path::_M_split_cmpts()): Likewise.
>
>Tested x86_64-linux, committed to gcc-8-branch.

This is the simpler patch for trunk and gcc-9-branch, which only needs
to change std::experimental::filesystem::path, because
std::filesystem::path already avoids any unnecessary allocations.

Tested powerpc64le-linux and x86_64-w64-mingw32 Committed to trunk so
far, backport to follow.


-------------- next part --------------
A non-text attachment was scrubbed...
Name: patch.txt
Type: text/x-patch
Size: 8613 bytes
Desc: not available
URL: <http://gcc.gnu.org/pipermail/libstdc++/attachments/20190528/dc374891/attachment.bin>