llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-clang Author: Timm Baeder (tbaederr) <details> <summary>Changes</summary> This fixes a long-standing FIXME item. Unfortunately it changes the diagnostic output of the tests added in `cxx23.cpp`, but they were wrong before and are wrong after, so no big deal. --- Full diff: https://github.com/llvm/llvm-project/pull/71919.diff 7 Files Affected: - (modified) clang/lib/AST/Interp/ByteCodeExprGen.cpp (+1-1) - (modified) clang/lib/AST/Interp/Interp.cpp (+34-10) - (modified) clang/lib/AST/Interp/Interp.h (+14) - (modified) clang/lib/AST/Interp/Opcodes.td (+1) - (modified) clang/test/AST/Interp/arrays.cpp (+32) - (modified) clang/test/AST/Interp/cxx23.cpp (+16-9) - (modified) clang/test/AST/Interp/literals.cpp (+24-3) ``````````diff diff --git a/clang/lib/AST/Interp/ByteCodeExprGen.cpp b/clang/lib/AST/Interp/ByteCodeExprGen.cpp index 15a717089660337..eca31efc85272bf 100644 --- a/clang/lib/AST/Interp/ByteCodeExprGen.cpp +++ b/clang/lib/AST/Interp/ByteCodeExprGen.cpp @@ -2125,7 +2125,7 @@ bool ByteCodeExprGen<Emitter>::visitDecl(const VarDecl *VD) { auto GlobalIndex = P.getGlobal(VD); assert(GlobalIndex); // visitVarDecl() didn't return false. if (VarT) { - if (!this->emitGetGlobal(*VarT, *GlobalIndex, VD)) + if (!this->emitGetGlobalUnchecked(*VarT, *GlobalIndex, VD)) return false; } else { if (!this->emitGetPtrGlobal(*GlobalIndex, VD)) diff --git a/clang/lib/AST/Interp/Interp.cpp b/clang/lib/AST/Interp/Interp.cpp index 144b674451e353c..d1d812a591591bf 100644 --- a/clang/lib/AST/Interp/Interp.cpp +++ b/clang/lib/AST/Interp/Interp.cpp @@ -53,6 +53,18 @@ static bool Jf(InterpState &S, CodePtr &PC, int32_t Offset) { return true; } +static void diagnoseNonConstVariable(InterpState &S, CodePtr OpPC, + const ValueDecl *VD) { + const SourceInfo &Loc = S.Current->getSource(OpPC); + S.FFDiag(Loc, + VD->getType()->isIntegralOrEnumerationType() + ? diag::note_constexpr_ltor_non_const_int + : diag::note_constexpr_ltor_non_constexpr, + 1) + << VD; + S.Note(VD->getLocation(), diag::note_declared_at); +} + static bool CheckActive(InterpState &S, CodePtr OpPC, const Pointer &Ptr, AccessKinds AK) { if (Ptr.isActive()) @@ -170,9 +182,7 @@ bool CheckExtern(InterpState &S, CodePtr OpPC, const Pointer &Ptr) { if (!S.checkingPotentialConstantExpression() && S.getLangOpts().CPlusPlus) { const auto *VD = Ptr.getDeclDesc()->asValueDecl(); - const SourceInfo &Loc = S.Current->getSource(OpPC); - S.FFDiag(Loc, diag::note_constexpr_ltor_non_constexpr, 1) << VD; - S.Note(VD->getLocation(), diag::note_declared_at); + diagnoseNonConstVariable(S, OpPC, VD); } return false; } @@ -215,6 +225,24 @@ bool CheckLive(InterpState &S, CodePtr OpPC, const Pointer &Ptr, return true; } +bool CheckConstant(InterpState &S, CodePtr OpPC, const Descriptor *Desc) { + assert(Desc); + if (const auto *D = Desc->asValueDecl()) { + if (const auto *VD = dyn_cast<VarDecl>(D); + VD && VD->hasGlobalStorage() && + !(VD->isConstexpr() || VD->getType().isConstQualified())) { + diagnoseNonConstVariable(S, OpPC, VD); + return false; + } + } + + return true; +} + +static bool CheckConstant(InterpState &S, CodePtr OpPC, const Pointer &Ptr) { + return CheckConstant(S, OpPC, Ptr.getDeclDesc()); +} + bool CheckDummy(InterpState &S, CodePtr OpPC, const Pointer &Ptr) { return !Ptr.isZero() && !Ptr.isDummy(); } @@ -303,6 +331,8 @@ bool CheckInitialized(InterpState &S, CodePtr OpPC, const Pointer &Ptr, bool CheckLoad(InterpState &S, CodePtr OpPC, const Pointer &Ptr) { if (!CheckDummy(S, OpPC, Ptr)) return false; + if (!CheckConstant(S, OpPC, Ptr)) + return false; if (!CheckLive(S, OpPC, Ptr, AK_Read)) return false; if (!CheckExtern(S, OpPC, Ptr)) @@ -601,13 +631,7 @@ bool CheckDeclRef(InterpState &S, CodePtr OpPC, const DeclRefExpr *DR) { } } else if (const auto *VD = dyn_cast<VarDecl>(D)) { if (!VD->getType().isConstQualified()) { - S.FFDiag(E, - VD->getType()->isIntegralOrEnumerationType() - ? diag::note_constexpr_ltor_non_const_int - : diag::note_constexpr_ltor_non_constexpr, - 1) - << VD; - S.Note(VD->getLocation(), diag::note_declared_at) << VD->getSourceRange(); + diagnoseNonConstVariable(S, OpPC, VD); return false; } diff --git a/clang/lib/AST/Interp/Interp.h b/clang/lib/AST/Interp/Interp.h index 7dd415d6e460536..5b7bd9916c02b57 100644 --- a/clang/lib/AST/Interp/Interp.h +++ b/clang/lib/AST/Interp/Interp.h @@ -78,6 +78,9 @@ bool CheckSubobject(InterpState &S, CodePtr OpPC, const Pointer &Ptr, /// Checks if a pointer points to const storage. bool CheckConst(InterpState &S, CodePtr OpPC, const Pointer &Ptr); +/// Checks if the Descriptor is of a constexpr or const global variable. +bool CheckConstant(InterpState &S, CodePtr OpPC, const Descriptor *Desc); + /// Checks if a pointer points to a mutable field. bool CheckMutable(InterpState &S, CodePtr OpPC, const Pointer &Ptr); @@ -1005,12 +1008,23 @@ bool SetThisField(InterpState &S, CodePtr OpPC, uint32_t I) { template <PrimType Name, class T = typename PrimConv<Name>::T> bool GetGlobal(InterpState &S, CodePtr OpPC, uint32_t I) { auto *B = S.P.getGlobal(I); + + if (!CheckConstant(S, OpPC, B->getDescriptor())) + return false; if (B->isExtern()) return false; S.Stk.push<T>(B->deref<T>()); return true; } +/// Same as GetGlobal, but without the checks. +template <PrimType Name, class T = typename PrimConv<Name>::T> +bool GetGlobalUnchecked(InterpState &S, CodePtr OpPC, uint32_t I) { + auto *B = S.P.getGlobal(I); + S.Stk.push<T>(B->deref<T>()); + return true; +} + template <PrimType Name, class T = typename PrimConv<Name>::T> bool SetGlobal(InterpState &S, CodePtr OpPC, uint32_t I) { // TODO: emit warning. diff --git a/clang/lib/AST/Interp/Opcodes.td b/clang/lib/AST/Interp/Opcodes.td index 69068e87d5720ab..e01b6b9eea7dbb4 100644 --- a/clang/lib/AST/Interp/Opcodes.td +++ b/clang/lib/AST/Interp/Opcodes.td @@ -379,6 +379,7 @@ def CheckGlobalCtor : Opcode {} // [] -> [Value] def GetGlobal : AccessOpcode; +def GetGlobalUnchecked : AccessOpcode; // [Value] -> [] def InitGlobal : AccessOpcode; // [Value] -> [] diff --git a/clang/test/AST/Interp/arrays.cpp b/clang/test/AST/Interp/arrays.cpp index 34e0086fb9ee8ca..91d64a9bd5e7d55 100644 --- a/clang/test/AST/Interp/arrays.cpp +++ b/clang/test/AST/Interp/arrays.cpp @@ -554,3 +554,35 @@ namespace GH69115 { static_assert(foo2() == 0, ""); #endif } + +namespace NonConstReads { +#if __cplusplus >= 202002L + void *p = nullptr; // ref-note {{declared here}} \ + // expected-note {{declared here}} + + int arr[!p]; // ref-error {{not allowed at file scope}} \ + // expected-error {{not allowed at file scope}} \ + // ref-warning {{variable length arrays}} \ + // ref-note {{read of non-constexpr variable 'p'}} \ + // expected-warning {{variable length arrays}} \ + // expected-note {{read of non-constexpr variable 'p'}} + int z; // ref-note {{declared here}} \ + // expected-note {{declared here}} + int a[z]; // ref-error {{not allowed at file scope}} \ + // expected-error {{not allowed at file scope}} \ + // ref-warning {{variable length arrays}} \ + // ref-note {{read of non-const variable 'z'}} \ + // expected-warning {{variable length arrays}} \ + // expected-note {{read of non-const variable 'z'}} +#else + void *p = nullptr; + int arr[!p]; // ref-error {{not allowed at file scope}} \ + // expected-error {{not allowed at file scope}} + int z; + int a[z]; // ref-error {{not allowed at file scope}} \ + // expected-error {{not allowed at file scope}} +#endif + + const int y = 0; + int yy[y]; +} diff --git a/clang/test/AST/Interp/cxx23.cpp b/clang/test/AST/Interp/cxx23.cpp index e284a66626fb331..4cd511f853571c4 100644 --- a/clang/test/AST/Interp/cxx23.cpp +++ b/clang/test/AST/Interp/cxx23.cpp @@ -4,9 +4,6 @@ // RUN: %clang_cc1 -std=c++23 -fsyntax-only -fcxx-exceptions -verify=expected23 %s -fexperimental-new-constant-interpreter -// expected23-no-diagnostics - - /// FIXME: The new interpreter is missing all the 'control flows through...' diagnostics. constexpr int f(int n) { // ref20-error {{constexpr function never produces a constant expression}} \ @@ -28,22 +25,32 @@ constexpr int g(int n) { // ref20-error {{constexpr function never produc } constexpr int c_thread_local(int n) { // ref20-error {{constexpr function never produces a constant expression}} \ - // ref23-error {{constexpr function never produces a constant expression}} + // ref23-error {{constexpr function never produces a constant expression}} \ + // expected20-error {{constexpr function never produces a constant expression}} \ + // expected23-error {{constexpr function never produces a constant expression}} static _Thread_local int m = 0; // ref20-note {{control flows through the definition of a thread_local variable}} \ // ref20-warning {{is a C++23 extension}} \ // ref23-note {{control flows through the definition of a thread_local variable}} \ - // expected20-warning {{is a C++23 extension}} - return m; + // expected20-warning {{is a C++23 extension}} \ + // expected20-note {{declared here}} \ + // expected23-note {{declared here}} + return m; // expected20-note {{read of non-const variable}} \ + // expected23-note {{read of non-const variable}} } constexpr int gnu_thread_local(int n) { // ref20-error {{constexpr function never produces a constant expression}} \ - // ref23-error {{constexpr function never produces a constant expression}} + // ref23-error {{constexpr function never produces a constant expression}} \ + // expected20-error {{constexpr function never produces a constant expression}} \ + // expected23-error {{constexpr function never produces a constant expression}} static __thread int m = 0; // ref20-note {{control flows through the definition of a thread_local variable}} \ // ref20-warning {{is a C++23 extension}} \ // ref23-note {{control flows through the definition of a thread_local variable}} \ - // expected20-warning {{is a C++23 extension}} - return m; + // expected20-warning {{is a C++23 extension}} \ + // expected20-note {{declared here}} \ + // expected23-note {{declared here}} + return m; // expected20-note {{read of non-const variable}} \ + // expected23-note {{read of non-const variable}} } constexpr int h(int n) { // ref20-error {{constexpr function never produces a constant expression}} \ diff --git a/clang/test/AST/Interp/literals.cpp b/clang/test/AST/Interp/literals.cpp index ba24955d14503be..0e472445b2d0e15 100644 --- a/clang/test/AST/Interp/literals.cpp +++ b/clang/test/AST/Interp/literals.cpp @@ -1156,8 +1156,29 @@ namespace InvalidDeclRefs { // expected-error {{not an integral constant expression}} \ // expected-note {{initializer of 'b02' is unknown}} - /// FIXME: This should also be diagnosed in the new interpreter. - int b03 = 3; // ref-note {{declared here}} + int b03 = 3; // ref-note {{declared here}} \ + // expected-note {{declared here}} static_assert(b03, ""); // ref-error {{not an integral constant expression}} \ - // ref-note {{read of non-const variable}} + // ref-note {{read of non-const variable}} \ + // expected-error {{not an integral constant expression}} \ + // expected-note {{read of non-const variable}} +} + +namespace NonConstReads { + void *p = nullptr; // ref-note {{declared here}} \ + // expected-note {{declared here}} + static_assert(!p, ""); // ref-error {{not an integral constant expression}} \ + // ref-note {{read of non-constexpr variable 'p'}} \ + // expected-error {{not an integral constant expression}} \ + // expected-note {{read of non-constexpr variable 'p'}} + + int arr[!p]; // ref-error {{variable length array}} \ + // expected-error {{variable length array}} + + int z; // ref-note {{declared here}} \ + // expected-note {{declared here}} + static_assert(z == 0, ""); // ref-error {{not an integral constant expression}} \ + // ref-note {{read of non-const variable 'z'}} \ + // expected-error {{not an integral constant expression}} \ + // expected-note {{read of non-const variable 'z'}} } `````````` </details> https://github.com/llvm/llvm-project/pull/71919 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
