Author: Timm Baeder Date: 2023-09-30T08:28:09+02:00 New Revision: 4909e7cac7100ee0bc9ce755ffab114d320ac0e3
URL: https://github.com/llvm/llvm-project/commit/4909e7cac7100ee0bc9ce755ffab114d320ac0e3 DIFF: https://github.com/llvm/llvm-project/commit/4909e7cac7100ee0bc9ce755ffab114d320ac0e3.diff LOG: [clang][Interp] Zero-init remaining string literal elements (#66862) Added: Modified: clang/lib/AST/Interp/ByteCodeExprGen.cpp clang/test/AST/Interp/arrays.cpp Removed: ################################################################################ diff --git a/clang/lib/AST/Interp/ByteCodeExprGen.cpp b/clang/lib/AST/Interp/ByteCodeExprGen.cpp index a09e2a007b912c9..46906377863bd74 100644 --- a/clang/lib/AST/Interp/ByteCodeExprGen.cpp +++ b/clang/lib/AST/Interp/ByteCodeExprGen.cpp @@ -881,8 +881,8 @@ bool ByteCodeExprGen<Emitter>::VisitStringLiteral(const StringLiteral *E) { // If the initializer string is too long, a diagnostic has already been // emitted. Read only the array length from the string literal. - unsigned N = - std::min(unsigned(CAT->getSize().getZExtValue()), E->getLength()); + unsigned ArraySize = CAT->getSize().getZExtValue(); + unsigned N = std::min(ArraySize, E->getLength()); size_t CharWidth = E->getCharByteWidth(); for (unsigned I = 0; I != N; ++I) { @@ -901,6 +901,23 @@ bool ByteCodeExprGen<Emitter>::VisitStringLiteral(const StringLiteral *E) { llvm_unreachable("unsupported character width"); } } + + // Fill up the rest of the char array with NUL bytes. + for (unsigned I = N; I != ArraySize; ++I) { + if (CharWidth == 1) { + this->emitConstSint8(0, E); + this->emitInitElemSint8(I, E); + } else if (CharWidth == 2) { + this->emitConstUint16(0, E); + this->emitInitElemUint16(I, E); + } else if (CharWidth == 4) { + this->emitConstUint32(0, E); + this->emitInitElemUint32(I, E); + } else { + llvm_unreachable("unsupported character width"); + } + } + return true; } diff --git a/clang/test/AST/Interp/arrays.cpp b/clang/test/AST/Interp/arrays.cpp index 7985f6841658e56..281835f828bbd7c 100644 --- a/clang/test/AST/Interp/arrays.cpp +++ b/clang/test/AST/Interp/arrays.cpp @@ -369,3 +369,24 @@ namespace ArrayInitLoop { static_assert(g() == 6); // expected-error {{failed}} \ // expected-note {{15 == 6}} } + +namespace StringZeroFill { + struct A { + char c[6]; + }; + constexpr A a = { "abc" }; + static_assert(a.c[0] == 'a', ""); + static_assert(a.c[1] == 'b', ""); + static_assert(a.c[2] == 'c', ""); + static_assert(a.c[3] == '\0', ""); + static_assert(a.c[4] == '\0', ""); + static_assert(a.c[5] == '\0', ""); + + constexpr char b[6] = "foo"; + static_assert(b[0] == 'f', ""); + static_assert(b[1] == 'o', ""); + static_assert(b[2] == 'o', ""); + static_assert(b[3] == '\0', ""); + static_assert(b[4] == '\0', ""); + static_assert(b[5] == '\0', ""); +} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
