Summary:
There isn't anything inherently wrong with returning a label from a
statement expression. In practice, the Linux kernel uses this pattern to
materialize PCs.
Fixes PR38569
Reviewers: niravd, rsmith, nickdesaulniers
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D50805
llvm-svn: 340101
} else if (isa<BlockExpr>(L)) {
Diag(DiagLoc, diag::err_ret_local_block) << DiagRange;
} else if (isa<AddrLabelExpr>(L)) {
+ // Don't warn when returning a label from a statement expression.
+ // Leaving the scope doesn't end its lifetime.
+ if (LK == LK_StmtExprResult)
+ return false;
Diag(DiagLoc, diag::warn_ret_addr_label) << DiagRange;
} else {
Diag(DiagLoc, diag::warn_ret_local_temp_addr_ref)
return &&bar; // expected-warning {{returning address of label, which is local}}
}
+// PR38569: Don't warn when returning a label from a statement expression.
+void test10_logpc(void*);
+void test10a() {
+ test10_logpc(({
+ my_pc:
+ &&my_pc;
+ }));
+}
+
// PR6034
void test11(int bit) {
switch (bit)