https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66192
Bug ID: 66192
Summary: C++ static initializer unnecessary __cxa_guard_acquire
for TARGET_RELAXED_ORDERING
Product: gcc
Version: 6.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: dje at gcc dot gnu.org
Target Milestone: ---
// static_init.cc
int* f(void) {
static int* p = new int;
return p;
}
$ g++ -O2 -S -fno-exceptions static_init.cc
generates an unnecessary call to __cxa_guard_acquire on what should be the fast
path for targets with TARGET_RELAXED_ORDERING defined. The guard should be an
atomic variable accessed with the equivalent of __atomic_load(ACQUIRE) instead
of a heavy-weight __cxa_guard_acquire() call invoking heavier-weight
synchronization.
