================
@@ -1230,11 +1230,26 @@ CodeGenFunction::EmitCXXForRangeStmt(const
CXXForRangeStmt &S,
JumpDest LoopExit = getJumpDestInCurrentScope("for.end");
LexicalScope ForScope(*this, S.getSourceRange());
+ const DeclStmt *RangeDS = cast<DeclStmt>(S.getRangeStmt());
+ const VarDecl *RangeVar = cast<VarDecl>(RangeDS->getSingleDecl());
+ if (getLangOpts().CPlusPlus23)
----------------
yronglin wrote:
The AST of `B{}` looks like the following. As far as I know, when I try to
debug the code generation of the temporary `Cleanups`, I found the following
steps.
Let M1 be `MaterializeTemporaryExpr 0x133830b80 <col:19, col:22> 'B' xvalue
extended by Var 0x133830940 '__range1' 'B &&'`
Let M2 be `MaterializeTemporaryExpr 0x1338305f0 <col:16, col:21> 'const A'
lvalue extended by Var 0x133830940 '__range1' 'B &&'`
Let C1 be `ExprWithCleanups 0x133830be8 <col:19, col:22> 'B' xvalue`.
Let C2 be `ExprWithCleanups 0x133830658 <line:10:16, col:21> 'const A' lvalue`
for each lifetime extended `MaterializeTemporaryExpr`
1. Handling M2, `CGF.pushLifetimeExtendedDestroy ` push a EHCleanup into
`EHStack` and push a NormalCleanup into `LifetimeExtendedCleanupStack`.
2. Handling C2, pop out the cleanup in `EHStack` and then push the copy of
cleanup which in `LifetimeExtendedCleanupStack` into `EHStack`, and resize
`LifetimeExtendedCleanupStack` to old size(0).
3. Handling M1, `CGF.pushLifetimeExtendedDestroy ` push a EHCleanup into
`EHStack` and push a NormalCleanup into `LifetimeExtendedCleanupStack`, now
`EHStack` has 2 cleanups(~B(), ~A()) and `LifetimeExtendedCleanupStack` has 1
cleanup(~B()).
4. Handling C1, pop out the top cleanup in `EHStack`, then emit the 2nd
cleanup(emit call of ~A() in a `entry` BB), finally, push the copy of
cleanup(~B()) which in `LifetimeExtendedCleanupStack` into `EHStack`, and
resize `LifetimeExtendedCleanupStack` to old size(0).
5. Back to EmitCXXForRangeStmt, there are 1 cleanup(~B()) in `EHStack`, then
`ForScope.ForceCleanup()` will emit this cleanup(call of ~B() in BB
`for.cleanup`).
After the above steps, even if the lifetime of A is bound to `__range`, it is
still not emit the expected cleanup.
```
`-CXXForRangeStmt 0x1338326d0 <line:17:3, col:36>
|-<<<NULL>>>
|-DeclStmt 0x133830d50 <col:19>
| `-VarDecl 0x133830940 <col:19, col:22> col:19 implicit used __range1 'B
&&' cinit
| `-ExprWithCleanups 0x133830be8 <col:19, col:22> 'B' xvalue
| `-MaterializeTemporaryExpr 0x133830b80 <col:19, col:22> 'B' xvalue
extended by Var 0x133830940 '__range1' 'B &&'
| `-CXXFunctionalCastExpr 0x1338307e0 <col:19, col:22> 'B'
functional cast to B <NoOp>
| `-InitListExpr 0x133830408 <col:20, col:22> 'B'
| |-IntegerLiteral 0x133829da0 <col:21> 'int' 0
| `-CXXDefaultInitExpr 0x133830670 <col:22> 'const A' lvalue
has rewritten init
| `-ExprWithCleanups 0x133830658 <line:10:16, col:21> 'const
A' lvalue
| `-MaterializeTemporaryExpr 0x1338305f0 <col:16, col:21>
'const A' lvalue extended by Var 0x133830940 '__range1' 'B &&'
| `-ImplicitCastExpr 0x1338305d8 <col:16, col:21> 'const
A' <NoOp>
| `-CXXFunctionalCastExpr 0x1338305b0 <col:16, col:21>
'A' functional cast to A <NoOp>
| `-CXXBindTemporaryExpr 0x133830590 <col:17, col:21>
'A' (CXXTemporary 0x133830590)
| `-InitListExpr 0x1338304f8 <col:17, col:21> 'A'
| `-InitListExpr 0x133830540 <col:18, col:20>
'int[1]'
| `-IntegerLiteral 0x1338297e8 <col:19> 'int' 0
```
https://github.com/llvm/llvm-project/pull/86960
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