[Bug libstdc++/94063] filesystem::path concatenation doesn't work for Windows root-paths
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94063 --- Comment #6 from Martin Liška --- commit r9-8369-g7ef07b622d8c2fca35813bf50669dcd663fe5cf2 Author: Jonathan Wakely Date: Thu Mar 12 17:39:05 2020 + libstdc++: Handle type-changing path concatenations (PR 94063) The filesystem::path::operator+= and filesystem::path::concat functions operate directly on the native format of the path and so can cause a path to mutate to a completely different type. For Windows combining a filename "x" with a filename ":" produces a root-name "x:". Similarly, a Cygwin root-directory "/" combined with a root-directory and filename "/x" produces a root-name "//x". Before this patch the implemenation didn't support those kind of mutations, assuming that concatenating two filenames would always produce a filename and concatenating with a root-dir would still have a root-dir. This patch fixes it simply by checking for the problem cases and creating a new path by re-parsing the result of the string concatenation. This is slightly suboptimal because the argument has already been parsed if it's a path, but more importantly it doesn't reuse any excess capacity that the path object being modified might already have allocated. Backport from mainline 2020-03-09 Jonathan Wakely PR libstdc++/94063 * src/c++17/fs_path.cc (path::operator+=(const path&)): Add kluge to handle concatenations that change the type of the first component. (path::operator+=(basic_string_view)): Likewise. * testsuite/27_io/filesystem/path/concat/94063.cc: New test.
[Bug libstdc++/94063] filesystem::path concatenation doesn't work for Windows root-paths
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94063 Jonathan Wakely changed: What|Removed |Added Status|ASSIGNED|RESOLVED Resolution|--- |FIXED --- Comment #5 from Jonathan Wakely --- Fixed for 9.4
[Bug libstdc++/94063] filesystem::path concatenation doesn't work for Windows root-paths
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94063 Martin Liška changed: What|Removed |Added CC||marxin at gcc dot gnu.org --- Comment #4 from Martin Liška --- commit r10-7095-gea182fe63634bb5b7913b3f1b6846e1900c5e0c4 Author: Jonathan Wakely Date: Mon Mar 9 23:22:57 2020 + libstdc++: Handle type-changing path concatenations (PR 94063) The filesystem::path::operator+= and filesystem::path::concat functions operate directly on the native format of the path and so can cause a path to mutate to a completely different type. For Windows combining a filename "x" with a filename ":" produces a root-name "x:". Similarly, a Cygwin root-directory "/" combined with a root-directory and filename "/x" produces a root-name "//x". Before this patch the implemenation didn't support those kind of mutations, assuming that concatenating two filenames would always produce a filename and concatenating with a root-dir would still have a root-dir. This patch fixes it simply by checking for the problem cases and creating a new path by re-parsing the result of the string concatenation. This is slightly suboptimal because the argument has already been parsed if it's a path, but more importantly it doesn't reuse any excess capacity that the path object being modified might already have allocated. That can be fixed later though. PR libstdc++/94063 * src/c++17/fs_path.cc (path::operator+=(const path&)): Add kluge to handle concatenations that change the type of the first component. (path::operator+=(basic_string_view)): Likewise. * testsuite/27_io/filesystem/path/concat/94063.cc: New test.
[Bug libstdc++/94063] filesystem::path concatenation doesn't work for Windows root-paths
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94063 Jonathan Wakely changed: What|Removed |Added Target Milestone|--- |9.4 Status|NEW |ASSIGNED --- Comment #3 from Jonathan Wakely --- Fixed for master with r10-7095-gea182fe63634bb5b7913b3f1b6846e1900c5e0c4 libstdc++: Handle type-changing path concatenations (PR 94063) The filesystem::path::operator+= and filesystem::path::concat functions operate directly on the native format of the path and so can cause a path to mutate to a completely different type. For Windows combining a filename "x" with a filename ":" produces a root-name "x:". Similarly, a Cygwin root-directory "/" combined with a root-directory and filename "/x" produces a root-name "//x". Before this patch the implemenation didn't support those kind of mutations, assuming that concatenating two filenames would always produce a filename and concatenating with a root-dir would still have a root-dir. This patch fixes it simply by checking for the problem cases and creating a new path by re-parsing the result of the string concatenation. This is slightly suboptimal because the argument has already been parsed if it's a path, but more importantly it doesn't reuse any excess capacity that the path object being modified might already have allocated. That can be fixed later though. PR libstdc++/94063 * src/c++17/fs_path.cc (path::operator+=(const path&)): Add kluge to handle concatenations that change the type of the first component. (path::operator+=(basic_string_view)): Likewise. * testsuite/27_io/filesystem/path/concat/94063.cc: New test. I plan to fix this for gcc 9.4 later. A more efficient fix would also be possible.
[Bug libstdc++/94063] filesystem::path concatenation doesn't work for Windows root-paths
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94063
--- Comment #2 from Jonathan Wakely ---
The test case for Cygwin (which is expected to fail on other targets) is
#include
#include
using std::filesystem::path;
int main()
{
path p;
p = "/";
p += path("/x");
assert( p.has_root_name() );
assert( p.root_name() == p );
p = "/";
p += "/x";
assert( p.has_root_name() );
assert( p.root_name() == p );
p = "/";
p += path("/");
assert( !p.has_root_name() );
assert( p.has_root_directory() );
p = "/";
p += "/";
assert( !p.has_root_name() );
assert( p.has_root_directory() );
}
[Bug libstdc++/94063] filesystem::path concatenation doesn't work for Windows root-paths
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94063
--- Comment #2 from Jonathan Wakely ---
Oops, the testcase is missing "using std::filesystem::path;"
There's a similar problem for Cygwin with path("/") += "/"
[Bug libstdc++/94063] filesystem::path concatenation doesn't work for Windows root-paths
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94063 --- Comment #1 from CVS Commits --- The master branch has been updated by Jonathan Wakely : https://gcc.gnu.org/g:180eeeaeb200a07f7f24e1f203cd026880ff861c commit r10-7062-g180eeeaeb200a07f7f24e1f203cd026880ff861c Author: Jonathan Wakely Date: Fri Mar 6 11:27:34 2020 + libstdc++: Fix failing filesystem::path tests (PR 93244) The checks for PR 93244 don't actually pass on Windows (which is the target where the bug is present) because of a different bug, PR 94063. This adjusts the tests to not be affected by 94063 so that they verify that 93244 was fixed. PR libstdc++/93244 * testsuite/27_io/filesystem/path/generic/generic_string.cc: Adjust test to not fail due to PR 94063. * testsuite/27_io/filesystem/path/generic/utf.cc: Likewise. * testsuite/27_io/filesystem/path/generic/wchar_t.cc: Likewise.
[Bug libstdc++/94063] filesystem::path concatenation doesn't work for Windows root-paths
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94063 Jonathan Wakely changed: What|Removed |Added Status|UNCONFIRMED |NEW Last reconfirmed||2020-03-05 Ever confirmed|0 |1 Known to fail||10.0, 9.2.0
