[compiler-rt] [NFCI][sanitizer] Refactor SIGNAL_INTERCEPTOR_SIGACTION_IMPL to not immediately return (PR #162916)

[Vitaly Buka via llvm-commits]

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@@ -57,7 +63,10 @@ INTERCEPTOR(uptr, signal, int signum, uptr handler) {
   SIGNAL_INTERCEPTOR_ENTER();
   if (GetHandleSignalMode(signum) == kHandleSignalExclusive)
     return (uptr) nullptr;
+
+  int ret;
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vitalybuka wrote:

Actually maybe better alternative do not change defines at all

int ret = +[](signal, signum, handler) {
   SIGNAL_INTERCEPTOR_SIGNAL_IMPL(signal, signum, handler);
}(signal, signum, handler);

https://github.com/llvm/llvm-project/pull/162916