diff options
author | John McCall <rjmccall@apple.com> | 2010-10-28 08:53:48 +0000 |
---|---|---|
committer | John McCall <rjmccall@apple.com> | 2010-10-28 08:53:48 +0000 |
commit | 95c225de9fa3d79f70ef5008c0279580a7d9dcad (patch) | |
tree | fd16d2e2abb0c26b1944dd5b666f9aa08404db14 /lib/Sema/JumpDiagnostics.cpp | |
parent | 3c7d7afd2530610e3d5678c4369731471d1bfb59 (diff) |
Implement an indirect-goto optimization for goto *&&lbl and respect this
in the scope checker. With that done, turn an indirect goto into a
protected scope into a hard error; otherwise IR generation has to start
worrying about declarations not dominating their scopes, as exemplified
in PR8473.
If this really affects anyone, I can probably adjust this to only hard-error
on possible indirect gotos into VLA scopes rather than arbitrary scopes.
But we'll see how people cope with the aggressive change on the marginal
feature.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@117539 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/Sema/JumpDiagnostics.cpp')
-rw-r--r-- | lib/Sema/JumpDiagnostics.cpp | 21 |
1 files changed, 20 insertions, 1 deletions
diff --git a/lib/Sema/JumpDiagnostics.cpp b/lib/Sema/JumpDiagnostics.cpp index b23f615af7..bbe7bd5b28 100644 --- a/lib/Sema/JumpDiagnostics.cpp +++ b/lib/Sema/JumpDiagnostics.cpp @@ -186,6 +186,17 @@ void JumpScopeChecker::BuildScopeInformation(Stmt *S, unsigned ParentScope) { break; case Stmt::IndirectGotoStmtClass: + // "goto *&&lbl;" is a special case which we treat as equivalent + // to a normal goto. In addition, we don't calculate scope in the + // operand (to avoid recording the address-of-label use), which + // works only because of the restricted set of expressions which + // we detect as constant targets. + if (cast<IndirectGotoStmt>(S)->getConstantTarget()) { + LabelAndGotoScopes[S] = ParentScope; + Jumps.push_back(S); + return; + } + LabelAndGotoScopes[S] = ParentScope; IndirectJumps.push_back(cast<IndirectGotoStmt>(S)); break; @@ -341,6 +352,14 @@ void JumpScopeChecker::VerifyJumps() { continue; } + // We only get indirect gotos here when they have a constant target. + if (IndirectGotoStmt *IGS = dyn_cast<IndirectGotoStmt>(Jump)) { + LabelStmt *Target = IGS->getConstantTarget(); + CheckJump(IGS, Target, IGS->getGotoLoc(), + diag::err_goto_into_protected_scope); + continue; + } + SwitchStmt *SS = cast<SwitchStmt>(Jump); for (SwitchCase *SC = SS->getSwitchCaseList(); SC; SC = SC->getNextSwitchCase()) { @@ -497,7 +516,7 @@ void JumpScopeChecker::DiagnoseIndirectJump(IndirectGotoStmt *Jump, unsigned TargetScope) { assert(JumpScope != TargetScope); - S.Diag(Jump->getGotoLoc(), diag::warn_indirect_goto_in_protected_scope); + S.Diag(Jump->getGotoLoc(), diag::err_indirect_goto_in_protected_scope); S.Diag(Target->getIdentLoc(), diag::note_indirect_goto_target); unsigned Common = GetDeepestCommonScope(JumpScope, TargetScope); |