On Wed, Aug 1, 2018 at 8:36 PM, Richard Smith <rich...@metafoo.co.uk> wrote: > On Tue, 31 Jul 2018, 23:06 Roman Lebedev via cfe-commits, > <cfe-commits@lists.llvm.org> wrote: >> >> Author: lebedevri >> Date: Tue Jul 31 23:06:16 2018 >> New Revision: 338489 >> >> URL: http://llvm.org/viewvc/llvm-project?rev=338489&view=rev >> Log: >> [AST] CastExpr: BasePathSize is not large enough. >> >> Summary: >> rC337815 / D49508 had to cannibalize one bit of >> `CastExprBitfields::BasePathSize` in order to squeeze `PartOfExplicitCast` >> boolean. >> That reduced the maximal value of `PartOfExplicitCast` from 9 bits (~512) >> down to 8 bits (~256). >> Apparently, that mattered. Too bad there weren't any tests. >> It caused [[ https://bugs.llvm.org/show_bug.cgi?id=38356 | PR38356 ]]. >> >> So we need to increase `PartOfExplicitCast` back at least to 9 bits, or a >> bit more. >> For obvious reasons, we can't do that in `CastExprBitfields` - that would >> blow up the size of every `Expr`. >> So we need to either just add a variable into the `CastExpr` (as done >> here), >> or use `llvm::TrailingObjects`. The latter does not seem to be >> straight-forward. >> Perhaps, that needs to be done not for the `CastExpr` itself, but for all >> of it's `final` children. >> >> Reviewers: rjmccall, rsmith, erichkeane >> >> Reviewed By: rjmccall >> >> Subscribers: bricci, hans, cfe-commits, waddlesplash >> >> Differential Revision: https://reviews.llvm.org/D50050 >> >> Added: >> cfe/trunk/test/CodeGenCXX/castexpr-basepathsize-threshold.cpp >> Modified: >> cfe/trunk/include/clang/AST/Expr.h >> cfe/trunk/include/clang/AST/ExprCXX.h >> cfe/trunk/include/clang/AST/ExprObjC.h >> cfe/trunk/include/clang/AST/Stmt.h >> cfe/trunk/lib/AST/Expr.cpp >> cfe/trunk/lib/AST/ExprCXX.cpp >> >> Modified: cfe/trunk/include/clang/AST/Expr.h >> URL: >> http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/AST/Expr.h?rev=338489&r1=338488&r2=338489&view=diff >> >> ============================================================================== >> --- cfe/trunk/include/clang/AST/Expr.h (original) >> +++ cfe/trunk/include/clang/AST/Expr.h Tue Jul 31 23:06:16 2018 >> @@ -2787,20 +2787,26 @@ public: >> /// representation in the source code (ExplicitCastExpr's derived >> /// classes). >> class CastExpr : public Expr { >> +public: >> + using BasePathSizeTy = unsigned int; >> + static_assert(std::numeric_limits<BasePathSizeTy>::max() >= 16384, >> + "[implimits] Direct and indirect base classes [16384]."); >> + >> private: >> Stmt *Op; >> >> bool CastConsistency() const; >> >> + BasePathSizeTy *BasePathSize(); >> + >> const CXXBaseSpecifier * const *path_buffer() const { >> return const_cast<CastExpr*>(this)->path_buffer(); >> } >> CXXBaseSpecifier **path_buffer(); >> >> - void setBasePathSize(unsigned basePathSize) { >> - CastExprBits.BasePathSize = basePathSize; >> - assert(CastExprBits.BasePathSize == basePathSize && >> - "basePathSize doesn't fit in bits of >> CastExprBits.BasePathSize!"); >> + void setBasePathSize(BasePathSizeTy basePathSize) { >> + assert(!path_empty() && basePathSize != 0); >> + *(BasePathSize()) = basePathSize; >> } >> >> protected: >> @@ -2823,7 +2829,9 @@ protected: >> Op(op) { >> CastExprBits.Kind = kind; >> CastExprBits.PartOfExplicitCast = false; >> - setBasePathSize(BasePathSize); >> + CastExprBits.BasePathIsEmpty = BasePathSize == 0; >> + if (!path_empty()) >> + setBasePathSize(BasePathSize); >> assert(CastConsistency()); >> } >> >> @@ -2831,7 +2839,9 @@ protected: >> CastExpr(StmtClass SC, EmptyShell Empty, unsigned BasePathSize) >> : Expr(SC, Empty) { >> CastExprBits.PartOfExplicitCast = false; >> - setBasePathSize(BasePathSize); >> + CastExprBits.BasePathIsEmpty = BasePathSize == 0; >> + if (!path_empty()) >> + setBasePathSize(BasePathSize); >> } >> >> public: >> @@ -2859,8 +2869,12 @@ public: >> >> typedef CXXBaseSpecifier **path_iterator; >> typedef const CXXBaseSpecifier * const *path_const_iterator; >> - bool path_empty() const { return CastExprBits.BasePathSize == 0; } >> - unsigned path_size() const { return CastExprBits.BasePathSize; } >> + bool path_empty() const { return CastExprBits.BasePathIsEmpty; } >> + unsigned path_size() const { >> + if (path_empty()) >> + return 0U; >> + return *(const_cast<CastExpr *>(this)->BasePathSize()); >> + } >> path_iterator path_begin() { return path_buffer(); } >> path_iterator path_end() { return path_buffer() + path_size(); } >> path_const_iterator path_begin() const { return path_buffer(); } >> @@ -2908,7 +2922,12 @@ public: >> /// @endcode >> class ImplicitCastExpr final >> : public CastExpr, >> - private llvm::TrailingObjects<ImplicitCastExpr, CXXBaseSpecifier *> >> { >> + private llvm::TrailingObjects<ImplicitCastExpr, >> CastExpr::BasePathSizeTy, >> + CXXBaseSpecifier *> { >> + size_t numTrailingObjects(OverloadToken<CastExpr::BasePathSizeTy>) >> const { >> + return path_empty() ? 0 : 1; >> + } >> + >> private: >> ImplicitCastExpr(QualType ty, CastKind kind, Expr *op, >> unsigned BasePathLength, ExprValueKind VK) >> @@ -3013,7 +3032,8 @@ public: >> /// (Type)expr. For example: @c (int)f. >> class CStyleCastExpr final >> : public ExplicitCastExpr, >> - private llvm::TrailingObjects<CStyleCastExpr, CXXBaseSpecifier *> { >> + private llvm::TrailingObjects<CStyleCastExpr, >> CastExpr::BasePathSizeTy, >> + CXXBaseSpecifier *> { >> SourceLocation LPLoc; // the location of the left paren >> SourceLocation RPLoc; // the location of the right paren >> >> @@ -3027,6 +3047,10 @@ class CStyleCastExpr final >> explicit CStyleCastExpr(EmptyShell Shell, unsigned PathSize) >> : ExplicitCastExpr(CStyleCastExprClass, Shell, PathSize) { } >> >> + size_t numTrailingObjects(OverloadToken<CastExpr::BasePathSizeTy>) >> const { >> + return path_empty() ? 0 : 1; >> + } >> + >> public: >> static CStyleCastExpr *Create(const ASTContext &Context, QualType T, >> ExprValueKind VK, CastKind K, >> >> Modified: cfe/trunk/include/clang/AST/ExprCXX.h >> URL: >> http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/AST/ExprCXX.h?rev=338489&r1=338488&r2=338489&view=diff >> >> ============================================================================== >> --- cfe/trunk/include/clang/AST/ExprCXX.h (original) >> +++ cfe/trunk/include/clang/AST/ExprCXX.h Tue Jul 31 23:06:16 2018 >> @@ -301,7 +301,8 @@ public: >> /// \c static_cast<int>(1.0). >> class CXXStaticCastExpr final >> : public CXXNamedCastExpr, >> - private llvm::TrailingObjects<CXXStaticCastExpr, CXXBaseSpecifier >> *> { >> + private llvm::TrailingObjects<CXXStaticCastExpr, >> CastExpr::BasePathSizeTy, >> + CXXBaseSpecifier *> { >> CXXStaticCastExpr(QualType ty, ExprValueKind vk, CastKind kind, Expr >> *op, >> unsigned pathSize, TypeSourceInfo *writtenTy, >> SourceLocation l, SourceLocation RParenLoc, >> @@ -312,6 +313,10 @@ class CXXStaticCastExpr final >> explicit CXXStaticCastExpr(EmptyShell Empty, unsigned PathSize) >> : CXXNamedCastExpr(CXXStaticCastExprClass, Empty, PathSize) {} >> >> + size_t numTrailingObjects(OverloadToken<CastExpr::BasePathSizeTy>) >> const { >> + return path_empty() ? 0 : 1; >> + } >> + >> public: >> friend class CastExpr; >> friend TrailingObjects; >> @@ -337,7 +342,8 @@ public: >> /// check to determine how to perform the type conversion. >> class CXXDynamicCastExpr final >> : public CXXNamedCastExpr, >> - private llvm::TrailingObjects<CXXDynamicCastExpr, CXXBaseSpecifier >> *> { >> + private llvm::TrailingObjects< >> + CXXDynamicCastExpr, CastExpr::BasePathSizeTy, CXXBaseSpecifier >> *> { >> CXXDynamicCastExpr(QualType ty, ExprValueKind VK, CastKind kind, >> Expr *op, unsigned pathSize, TypeSourceInfo >> *writtenTy, >> SourceLocation l, SourceLocation RParenLoc, >> @@ -348,6 +354,10 @@ class CXXDynamicCastExpr final >> explicit CXXDynamicCastExpr(EmptyShell Empty, unsigned pathSize) >> : CXXNamedCastExpr(CXXDynamicCastExprClass, Empty, pathSize) {} >> >> + size_t numTrailingObjects(OverloadToken<CastExpr::BasePathSizeTy>) >> const { >> + return path_empty() ? 0 : 1; >> + } >> + >> public: >> friend class CastExpr; >> friend TrailingObjects; >> @@ -380,6 +390,7 @@ public: >> class CXXReinterpretCastExpr final >> : public CXXNamedCastExpr, >> private llvm::TrailingObjects<CXXReinterpretCastExpr, >> + CastExpr::BasePathSizeTy, >> CXXBaseSpecifier *> { >> CXXReinterpretCastExpr(QualType ty, ExprValueKind vk, CastKind kind, >> Expr *op, unsigned pathSize, >> @@ -392,6 +403,10 @@ class CXXReinterpretCastExpr final >> CXXReinterpretCastExpr(EmptyShell Empty, unsigned pathSize) >> : CXXNamedCastExpr(CXXReinterpretCastExprClass, Empty, pathSize) {} >> >> + size_t numTrailingObjects(OverloadToken<CastExpr::BasePathSizeTy>) >> const { >> + return path_empty() ? 0 : 1; >> + } >> + >> public: >> friend class CastExpr; >> friend TrailingObjects; >> @@ -419,7 +434,8 @@ public: >> /// value. >> class CXXConstCastExpr final >> : public CXXNamedCastExpr, >> - private llvm::TrailingObjects<CXXConstCastExpr, CXXBaseSpecifier *> >> { >> + private llvm::TrailingObjects<CXXConstCastExpr, >> CastExpr::BasePathSizeTy, >> + CXXBaseSpecifier *> { >> CXXConstCastExpr(QualType ty, ExprValueKind VK, Expr *op, >> TypeSourceInfo *writtenTy, SourceLocation l, >> SourceLocation RParenLoc, SourceRange AngleBrackets) >> @@ -429,6 +445,10 @@ class CXXConstCastExpr final >> explicit CXXConstCastExpr(EmptyShell Empty) >> : CXXNamedCastExpr(CXXConstCastExprClass, Empty, 0) {} >> >> + size_t numTrailingObjects(OverloadToken<CastExpr::BasePathSizeTy>) >> const { >> + return path_empty() ? 0 : 1; >> + } >> + >> public: >> friend class CastExpr; >> friend TrailingObjects; >> @@ -1471,7 +1491,8 @@ public: >> /// \endcode >> class CXXFunctionalCastExpr final >> : public ExplicitCastExpr, >> - private llvm::TrailingObjects<CXXFunctionalCastExpr, >> CXXBaseSpecifier *> { >> + private llvm::TrailingObjects< >> + CXXFunctionalCastExpr, CastExpr::BasePathSizeTy, >> CXXBaseSpecifier *> { >> SourceLocation LParenLoc; >> SourceLocation RParenLoc; >> >> @@ -1486,6 +1507,10 @@ class CXXFunctionalCastExpr final >> explicit CXXFunctionalCastExpr(EmptyShell Shell, unsigned PathSize) >> : ExplicitCastExpr(CXXFunctionalCastExprClass, Shell, PathSize) {} >> >> + size_t numTrailingObjects(OverloadToken<CastExpr::BasePathSizeTy>) >> const { >> + return path_empty() ? 0 : 1; >> + } >> + >> public: >> friend class CastExpr; >> friend TrailingObjects; >> >> Modified: cfe/trunk/include/clang/AST/ExprObjC.h >> URL: >> http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/AST/ExprObjC.h?rev=338489&r1=338488&r2=338489&view=diff >> >> ============================================================================== >> --- cfe/trunk/include/clang/AST/ExprObjC.h (original) >> +++ cfe/trunk/include/clang/AST/ExprObjC.h Tue Jul 31 23:06:16 2018 >> @@ -1571,7 +1571,8 @@ public: >> /// \endcode >> class ObjCBridgedCastExpr final >> : public ExplicitCastExpr, >> - private llvm::TrailingObjects<ObjCBridgedCastExpr, CXXBaseSpecifier >> *> { >> + private llvm::TrailingObjects< >> + ObjCBridgedCastExpr, CastExpr::BasePathSizeTy, CXXBaseSpecifier >> *> { >> friend class ASTStmtReader; >> friend class ASTStmtWriter; >> friend class CastExpr; >> @@ -1581,6 +1582,10 @@ class ObjCBridgedCastExpr final >> SourceLocation BridgeKeywordLoc; >> unsigned Kind : 2; >> >> + size_t numTrailingObjects(OverloadToken<CastExpr::BasePathSizeTy>) >> const { >> + return path_empty() ? 0 : 1; >> + } >> + >> public: >> ObjCBridgedCastExpr(SourceLocation LParenLoc, ObjCBridgeCastKind Kind, >> CastKind CK, SourceLocation BridgeKeywordLoc, >> >> Modified: cfe/trunk/include/clang/AST/Stmt.h >> URL: >> http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/AST/Stmt.h?rev=338489&r1=338488&r2=338489&view=diff >> >> ============================================================================== >> --- cfe/trunk/include/clang/AST/Stmt.h (original) >> +++ cfe/trunk/include/clang/AST/Stmt.h Tue Jul 31 23:06:16 2018 >> @@ -204,7 +204,7 @@ protected: >> >> unsigned Kind : 6; >> unsigned PartOfExplicitCast : 1; // Only set for ImplicitCastExpr. >> - unsigned BasePathSize : 32 - 6 - 1 - NumExprBits; >> + unsigned BasePathIsEmpty : 1; >> }; >> >> class CallExprBitfields { >> >> Modified: cfe/trunk/lib/AST/Expr.cpp >> URL: >> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/AST/Expr.cpp?rev=338489&r1=338488&r2=338489&view=diff >> >> ============================================================================== >> --- cfe/trunk/lib/AST/Expr.cpp (original) >> +++ cfe/trunk/lib/AST/Expr.cpp Tue Jul 31 23:06:16 2018 >> @@ -1734,6 +1734,21 @@ NamedDecl *CastExpr::getConversionFuncti >> return nullptr; >> } >> >> +CastExpr::BasePathSizeTy *CastExpr::BasePathSize() { >> + assert(!path_empty()); >> + switch (getStmtClass()) { >> +#define ABSTRACT_STMT(x) >> +#define CASTEXPR(Type, Base) >> \ >> + case Stmt::Type##Class: >> \ >> + return static_cast<Type *>(this) >> \ >> + ->getTrailingObjects<CastExpr::BasePathSizeTy>(); >> +#define STMT(Type, Base) >> +#include "clang/AST/StmtNodes.inc" >> + default: >> + llvm_unreachable("non-cast expressions not possible here"); >> + } >> +} >> + >> CXXBaseSpecifier **CastExpr::path_buffer() { >> switch (getStmtClass()) { >> #define ABSTRACT_STMT(x) >> @@ -1772,7 +1787,9 @@ ImplicitCastExpr *ImplicitCastExpr::Crea >> const CXXCastPath *BasePath, >> ExprValueKind VK) { >> unsigned PathSize = (BasePath ? BasePath->size() : 0); >> - void *Buffer = C.Allocate(totalSizeToAlloc<CXXBaseSpecifier >> *>(PathSize)); >> + void *Buffer = >> + C.Allocate(totalSizeToAlloc<CastExpr::BasePathSizeTy, >> CXXBaseSpecifier *>( >> + PathSize ? 1 : 0, PathSize)); >> ImplicitCastExpr *E = >> new (Buffer) ImplicitCastExpr(T, Kind, Operand, PathSize, VK); >> if (PathSize) >> @@ -1783,7 +1800,9 @@ ImplicitCastExpr *ImplicitCastExpr::Crea >> >> ImplicitCastExpr *ImplicitCastExpr::CreateEmpty(const ASTContext &C, >> unsigned PathSize) { >> - void *Buffer = C.Allocate(totalSizeToAlloc<CXXBaseSpecifier >> *>(PathSize)); >> + void *Buffer = >> + C.Allocate(totalSizeToAlloc<CastExpr::BasePathSizeTy, >> CXXBaseSpecifier *>( >> + PathSize ? 1 : 0, PathSize)); >> return new (Buffer) ImplicitCastExpr(EmptyShell(), PathSize); >> } >> >> @@ -1794,7 +1813,9 @@ CStyleCastExpr *CStyleCastExpr::Create(c >> TypeSourceInfo *WrittenTy, >> SourceLocation L, SourceLocation >> R) { >> unsigned PathSize = (BasePath ? BasePath->size() : 0); >> - void *Buffer = C.Allocate(totalSizeToAlloc<CXXBaseSpecifier >> *>(PathSize)); >> + void *Buffer = >> + C.Allocate(totalSizeToAlloc<CastExpr::BasePathSizeTy, >> CXXBaseSpecifier *>( >> + PathSize ? 1 : 0, PathSize)); >> CStyleCastExpr *E = >> new (Buffer) CStyleCastExpr(T, VK, K, Op, PathSize, WrittenTy, L, R); >> if (PathSize) >> @@ -1805,7 +1826,9 @@ CStyleCastExpr *CStyleCastExpr::Create(c >> >> CStyleCastExpr *CStyleCastExpr::CreateEmpty(const ASTContext &C, >> unsigned PathSize) { >> - void *Buffer = C.Allocate(totalSizeToAlloc<CXXBaseSpecifier >> *>(PathSize)); >> + void *Buffer = >> + C.Allocate(totalSizeToAlloc<CastExpr::BasePathSizeTy, >> CXXBaseSpecifier *>( >> + PathSize ? 1 : 0, PathSize)); >> return new (Buffer) CStyleCastExpr(EmptyShell(), PathSize); >> } >> >> >> Modified: cfe/trunk/lib/AST/ExprCXX.cpp >> URL: >> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/AST/ExprCXX.cpp?rev=338489&r1=338488&r2=338489&view=diff >> >> ============================================================================== >> --- cfe/trunk/lib/AST/ExprCXX.cpp (original) >> +++ cfe/trunk/lib/AST/ExprCXX.cpp Tue Jul 31 23:06:16 2018 >> @@ -559,7 +559,9 @@ CXXStaticCastExpr *CXXStaticCastExpr::Cr >> SourceLocation RParenLoc, >> SourceRange AngleBrackets) { >> unsigned PathSize = (BasePath ? BasePath->size() : 0); >> - void *Buffer = C.Allocate(totalSizeToAlloc<CXXBaseSpecifier >> *>(PathSize)); >> + void *Buffer = >> + C.Allocate(totalSizeToAlloc<CastExpr::BasePathSizeTy, >> CXXBaseSpecifier *>( >> + PathSize ? 1 : 0, PathSize)); >> auto *E = >> new (Buffer) CXXStaticCastExpr(T, VK, K, Op, PathSize, WrittenTy, >> L, >> RParenLoc, AngleBrackets); >> @@ -571,7 +573,9 @@ CXXStaticCastExpr *CXXStaticCastExpr::Cr >> >> CXXStaticCastExpr *CXXStaticCastExpr::CreateEmpty(const ASTContext &C, >> unsigned PathSize) { >> - void *Buffer = C.Allocate(totalSizeToAlloc<CXXBaseSpecifier >> *>(PathSize)); >> + void *Buffer = >> + C.Allocate(totalSizeToAlloc<CastExpr::BasePathSizeTy, >> CXXBaseSpecifier *>( >> + PathSize ? 1 : 0, PathSize)); >> return new (Buffer) CXXStaticCastExpr(EmptyShell(), PathSize); >> } >> >> @@ -584,7 +588,9 @@ CXXDynamicCastExpr *CXXDynamicCastExpr:: >> SourceLocation RParenLoc, >> SourceRange AngleBrackets) >> { >> unsigned PathSize = (BasePath ? BasePath->size() : 0); >> - void *Buffer = C.Allocate(totalSizeToAlloc<CXXBaseSpecifier >> *>(PathSize)); >> + void *Buffer = >> + C.Allocate(totalSizeToAlloc<CastExpr::BasePathSizeTy, >> CXXBaseSpecifier *>( >> + PathSize ? 1 : 0, PathSize)); >> auto *E = >> new (Buffer) CXXDynamicCastExpr(T, VK, K, Op, PathSize, WrittenTy, >> L, >> RParenLoc, AngleBrackets); >> @@ -596,7 +602,9 @@ CXXDynamicCastExpr *CXXDynamicCastExpr:: >> >> CXXDynamicCastExpr *CXXDynamicCastExpr::CreateEmpty(const ASTContext &C, >> unsigned PathSize) { >> - void *Buffer = C.Allocate(totalSizeToAlloc<CXXBaseSpecifier >> *>(PathSize)); >> + void *Buffer = >> + C.Allocate(totalSizeToAlloc<CastExpr::BasePathSizeTy, >> CXXBaseSpecifier *>( >> + PathSize ? 1 : 0, PathSize)); >> return new (Buffer) CXXDynamicCastExpr(EmptyShell(), PathSize); >> } >> >> @@ -641,7 +649,9 @@ CXXReinterpretCastExpr::Create(const AST >> SourceLocation RParenLoc, >> SourceRange AngleBrackets) { >> unsigned PathSize = (BasePath ? BasePath->size() : 0); >> - void *Buffer = C.Allocate(totalSizeToAlloc<CXXBaseSpecifier >> *>(PathSize)); >> + void *Buffer = >> + C.Allocate(totalSizeToAlloc<CastExpr::BasePathSizeTy, >> CXXBaseSpecifier *>( >> + PathSize ? 1 : 0, PathSize)); >> auto *E = >> new (Buffer) CXXReinterpretCastExpr(T, VK, K, Op, PathSize, >> WrittenTy, L, >> RParenLoc, AngleBrackets); >> @@ -653,7 +663,9 @@ CXXReinterpretCastExpr::Create(const AST >> >> CXXReinterpretCastExpr * >> CXXReinterpretCastExpr::CreateEmpty(const ASTContext &C, unsigned >> PathSize) { >> - void *Buffer = C.Allocate(totalSizeToAlloc<CXXBaseSpecifier >> *>(PathSize)); >> + void *Buffer = >> + C.Allocate(totalSizeToAlloc<CastExpr::BasePathSizeTy, >> CXXBaseSpecifier *>( >> + PathSize ? 1 : 0, PathSize)); >> return new (Buffer) CXXReinterpretCastExpr(EmptyShell(), PathSize); >> } >> >> @@ -676,7 +688,9 @@ CXXFunctionalCastExpr::Create(const ASTC >> const CXXCastPath *BasePath, >> SourceLocation L, SourceLocation R) { >> unsigned PathSize = (BasePath ? BasePath->size() : 0); >> - void *Buffer = C.Allocate(totalSizeToAlloc<CXXBaseSpecifier >> *>(PathSize)); >> + void *Buffer = >> + C.Allocate(totalSizeToAlloc<CastExpr::BasePathSizeTy, >> CXXBaseSpecifier *>( >> + PathSize ? 1 : 0, PathSize)); >> auto *E = >> new (Buffer) CXXFunctionalCastExpr(T, VK, Written, K, Op, PathSize, >> L, R); >> if (PathSize) >> @@ -687,7 +701,9 @@ CXXFunctionalCastExpr::Create(const ASTC >> >> CXXFunctionalCastExpr * >> CXXFunctionalCastExpr::CreateEmpty(const ASTContext &C, unsigned >> PathSize) { >> - void *Buffer = C.Allocate(totalSizeToAlloc<CXXBaseSpecifier >> *>(PathSize)); >> + void *Buffer = >> + C.Allocate(totalSizeToAlloc<CastExpr::BasePathSizeTy, >> CXXBaseSpecifier *>( >> + PathSize ? 1 : 0, PathSize)); >> return new (Buffer) CXXFunctionalCastExpr(EmptyShell(), PathSize); >> } >> >> >> Added: cfe/trunk/test/CodeGenCXX/castexpr-basepathsize-threshold.cpp >> URL: >> http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenCXX/castexpr-basepathsize-threshold.cpp?rev=338489&view=auto >> >> ============================================================================== >> --- cfe/trunk/test/CodeGenCXX/castexpr-basepathsize-threshold.cpp (added) >> +++ cfe/trunk/test/CodeGenCXX/castexpr-basepathsize-threshold.cpp Tue Jul >> 31 23:06:16 2018 >> @@ -0,0 +1,27 @@ >> +// RUN: %clang_cc1 %s -emit-llvm -o - > > > Please use -emit-llvm-only here rather than writing the IR to stdout. Oh, sorry, good to know. Thanks for telling me. I will commit a fix shortly.
>> + >> +// https://bugs.llvm.org/show_bug.cgi?id=38356 >> +// We only check that we do not crash. >> + >> +template <typename a, a b(unsigned), int c, unsigned...> >> +struct d : d<a, b, c - 1> {}; >> +template <typename a, a b(unsigned), unsigned... e> >> +struct d<a, b, 0, e...> { >> + a f[0]; >> +}; >> +struct g { >> + static g h(unsigned); >> +}; >> +struct i { >> + void j() const; >> + // Current maximum depth of recursive template instantiation is 1024, >> + // thus, this \/ threshold value is used here. BasePathSize in CastExpr >> might >> + // not fit it, so we are testing that we do fit it. >> + // If -ftemplate-depth= is provided, larger values (4096 and up) cause >> crashes >> + // elsewhere. >> + d<g, g::h, (1U << 10U) - 2U> f; >> +}; >> +void i::j() const { >> + const void *k{f.f}; >> + (void)k; >> +} >> >> >> _______________________________________________ >> cfe-commits mailing list >> cfe-commits@lists.llvm.org >> http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
