Author: Guillaume Chatelet Date: 2020-03-21T12:42:06+01:00 New Revision: d260a10d98dff6e34d081e570df1f7c0a50b9a73
URL: https://github.com/llvm/llvm-project/commit/d260a10d98dff6e34d081e570df1f7c0a50b9a73 DIFF: https://github.com/llvm/llvm-project/commit/d260a10d98dff6e34d081e570df1f7c0a50b9a73.diff LOG: [clang] Fix crash during template sema checking Summary: If the size parameter of `__builtin_memcpy_inline` comes from an un-instantiated template parameter current code would crash. Reviewers: efriedma, courbet Subscribers: cfe-commits Tags: #clang Differential Revision: https://reviews.llvm.org/D76504 Added: clang/test/Sema/builtins-memcpy-inline.cpp Modified: clang/lib/Sema/SemaChecking.cpp Removed: clang/test/Sema/builtins-memcpy-inline.c ################################################################################ diff --git a/clang/lib/Sema/SemaChecking.cpp b/clang/lib/Sema/SemaChecking.cpp index 8a2b4b019663..c3e168c1e736 100644 --- a/clang/lib/Sema/SemaChecking.cpp +++ b/clang/lib/Sema/SemaChecking.cpp @@ -1649,11 +1649,16 @@ Sema::CheckBuiltinFunctionCall(FunctionDecl *FDecl, unsigned BuiltinID, case Builtin::BI__builtin_nontemporal_store: return SemaBuiltinNontemporalOverloaded(TheCallResult); case Builtin::BI__builtin_memcpy_inline: { - // __builtin_memcpy_inline size argument is a constant by definition. - if (TheCall->getArg(2)->EvaluateKnownConstInt(Context).isNullValue()) + clang::Expr *SizeOp = TheCall->getArg(2); + // We warn about copying to or from `nullptr` pointers when `size` is + // greater than 0. When `size` is value dependent we cannot evaluate its + // value so we bail out. + if (SizeOp->isValueDependent()) break; - CheckNonNullArgument(*this, TheCall->getArg(0), TheCall->getExprLoc()); - CheckNonNullArgument(*this, TheCall->getArg(1), TheCall->getExprLoc()); + if (!SizeOp->EvaluateKnownConstInt(Context).isNullValue()) { + CheckNonNullArgument(*this, TheCall->getArg(0), TheCall->getExprLoc()); + CheckNonNullArgument(*this, TheCall->getArg(1), TheCall->getExprLoc()); + } break; } #define BUILTIN(ID, TYPE, ATTRS) diff --git a/clang/test/Sema/builtins-memcpy-inline.c b/clang/test/Sema/builtins-memcpy-inline.cpp similarity index 86% rename from clang/test/Sema/builtins-memcpy-inline.c rename to clang/test/Sema/builtins-memcpy-inline.cpp index 6d0edce92a11..5e03a975a71b 100644 --- a/clang/test/Sema/builtins-memcpy-inline.c +++ b/clang/test/Sema/builtins-memcpy-inline.cpp @@ -30,3 +30,9 @@ void test_memcpy_inline_null_buffer_is_ok_if_size_is_zero(void *ptr) { void test_memcpy_inline_non_constant_size(void *dst, const void *src, unsigned size) { __builtin_memcpy_inline(dst, src, size); // expected-error {{argument to '__builtin_memcpy_inline' must be a constant integer}} } + +template <unsigned size> +void test_memcpy_inline_template(void *dst, const void *src) { + // we do not try to evaluate size in non intantiated templates. + __builtin_memcpy_inline(dst, src, size); +} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
