diff options
author | Vassil Vassilev <v.g.vassilev@gmail.com> | 2016-04-27 10:46:06 +0000 |
---|---|---|
committer | Vassil Vassilev <v.g.vassilev@gmail.com> | 2016-04-27 10:46:06 +0000 |
commit | ff118bbb13ec447bf7d2c138b8e2e85b75afd72b (patch) | |
tree | 6afab439c188237a010fe15901a579789894ee06 /lib/AST/DeclBase.cpp | |
parent | e57bbbecd02c963312189f829a3af93cda3c9b58 (diff) |
[modules] Fix Decl's Used invariant.
The Decl::isUsed has a value for every decl. In non-module builds it is very
difficult (but possible) to break this invariant but when we walk up the redecl
chain we find the neccessary information.
When deserializing the decls from a module it is much more difficult to update
correctly this invariant. The patch centralizes the information whether a decl
is used in the canonical decl marking the entire entity as being used.
Fixes https://llvm.org/bugs/show_bug.cgi?id=27401
Patch by Cristina Cristescu and me.
Thanks to Richard Smith who helped to debug and understand the issue!
Reviewed by Richard Smith.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@267691 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/AST/DeclBase.cpp')
-rw-r--r-- | lib/AST/DeclBase.cpp | 18 |
1 files changed, 11 insertions, 7 deletions
diff --git a/lib/AST/DeclBase.cpp b/lib/AST/DeclBase.cpp index aec3b7cd3b..338b059e53 100644 --- a/lib/AST/DeclBase.cpp +++ b/lib/AST/DeclBase.cpp @@ -340,25 +340,29 @@ unsigned Decl::getMaxAlignment() const { return Align; } -bool Decl::isUsed(bool CheckUsedAttr) const { - if (Used) +bool Decl::isUsed(bool CheckUsedAttr) const { + const Decl *CanonD = getCanonicalDecl(); + if (CanonD->Used) return true; - + // Check for used attribute. - if (CheckUsedAttr && hasAttr<UsedAttr>()) + // Ask the most recent decl, since attributes accumulate in the redecl chain. + if (CheckUsedAttr && getMostRecentDecl()->hasAttr<UsedAttr>()) return true; - return false; + // The information may have not been deserialized yet. Force deserialization + // to complete the needed information. + return getMostRecentDecl()->getCanonicalDecl()->Used; } void Decl::markUsed(ASTContext &C) { - if (Used) + if (isUsed()) return; if (C.getASTMutationListener()) C.getASTMutationListener()->DeclarationMarkedUsed(this); - Used = true; + setIsUsed(); } bool Decl::isReferenced() const { |