Clang should no longer incorrectly diagnose a variable declaration inside of a
lambda expression that shares the name of a variable in a containing
if/while/for/switch init statement as a redeclaration.
After this patch, clang is supposed to accept code below:
void foo() {
for (int x = [] { int x = 0; return x; }(); ;) ;
}
Fixes https://github.com/llvm/llvm-project/issues/54913
Differential Revision: https://reviews.llvm.org/D123840
Rather than sprinkle calls to DiagnoseUnusedExprResult() around in places where we want diagnostics, we now diagnose unused expression statements and full expressions in a more generic way when acting on the final expression statement. This results in more appropriate diagnostics for [[nodiscard]] where we were previously lacking them, such as when the body of a for loop is not a compound statement.
This patch fixes PR39837.
llvm-svn: 350404