https://gcc.gnu.org/bugzilla/show_bug.cgi?id=122565
Bug ID: 122565
Summary: RISC-V: libstdc++ using mutexes (vs. atomics)
Product: gcc
Version: 15.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
Assignee: unassigned at gcc dot gnu.org
Reporter: vineetg at gcc dot gnu.org
CC: bergner at oss dot tenstorrent.com, jeffreyalaw at gmail
dot com,
rdapp at gcc dot gnu.org
Target Milestone: ---
libstdc++ for RISC-V always falls back to using mutexes which could be
sub-optimal for C++ intensive workloads. This was deliberately done as
3fc22eedb033 ("libstdc++: Default to mutex-based atomics on RISC-V") as fix for
bug 84568
At the time, RISC-V lacked inline atomics and recently another gating issue bug
81358 for automatic linking of libatomic was addressed too
As discussed in Patchworks call this morning, opening this PR so we can see if
anything can be done about this (maybe a flag-day which addresses this and a
bunch of other long standing issues).
