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// RUN: %clangxx_msan -fsanitize-memory-track-origins=2 -O1 %s -o %t && not %run %t 2>&1 | FileCheck %s
// musl does not define FP_XSTATE_MAGIC1.
// REQUIRES: x86_64-target-arch && glibc-2.27
#include <pthread.h>
#include <signal.h>
#include <stdint.h>
#include <ucontext.h>
void handler(int sig, siginfo_t *info, void *uctx) {
volatile int uninit;
auto *mctx = &static_cast<ucontext_t *>(uctx)->uc_mcontext;
auto *fpregs = mctx->fpregs;
// The member names differ across header versions, but the actual layout
// is always the same. So avoid using members, just use arithmetic.
const uint32_t *after_xmm =
reinterpret_cast<const uint32_t *>(fpregs + 1) - 24;
if (after_xmm[12] == FP_XSTATE_MAGIC1)
reinterpret_cast<_xstate *>(mctx->fpregs)->ymmh.ymmh_space[0] = uninit;
else
mctx->gregs[REG_RAX] = uninit;
}
int main(int argc, char **argv) {
struct sigaction act = {};
act.sa_sigaction = handler;
act.sa_flags = SA_SIGINFO;
sigfillset(&act.sa_mask);
sigaction(SIGPROF, &act, 0);
pthread_kill(pthread_self(), SIGPROF);
return 0;
}
// CHECK: WARNING: MemorySanitizer:
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