llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-clang-analysis Author: Max (mxms0) <details> <summary>Changes</summary> Do not warn if the index is an enum and we an determine statically that it's within bounds. --- Full diff: https://github.com/llvm/llvm-project/pull/117370.diff 2 Files Affected: - (modified) clang/lib/Analysis/UnsafeBufferUsage.cpp (+7) - (modified) clang/test/SemaCXX/warn-unsafe-buffer-usage-array.cpp (+17) ``````````diff diff --git a/clang/lib/Analysis/UnsafeBufferUsage.cpp b/clang/lib/Analysis/UnsafeBufferUsage.cpp index 5f36ffa926b269..addb724e2e2c9a 100644 --- a/clang/lib/Analysis/UnsafeBufferUsage.cpp +++ b/clang/lib/Analysis/UnsafeBufferUsage.cpp @@ -463,6 +463,13 @@ AST_MATCHER(ArraySubscriptExpr, isSafeArraySubscript) { return true; } + // Array index wasn't an integer literal, let's see if it was an enum or + // something similar + const auto IntConst = Node.getIdx()->getIntegerConstantExpr(Finder->getASTContext()); + if (IntConst && *IntConst > 0 && *IntConst < size) { + return true; + } + return false; } diff --git a/clang/test/SemaCXX/warn-unsafe-buffer-usage-array.cpp b/clang/test/SemaCXX/warn-unsafe-buffer-usage-array.cpp index c6c93a27e4b969..a65ecdf39edfcc 100644 --- a/clang/test/SemaCXX/warn-unsafe-buffer-usage-array.cpp +++ b/clang/test/SemaCXX/warn-unsafe-buffer-usage-array.cpp @@ -39,6 +39,23 @@ void constant_idx_unsafe(unsigned idx) { buffer[10] = 0; // expected-note{{used in buffer access here}} } +enum FooEnum { + A = 0, + B = 1, + C = 2, + D +}; + +void constant_enum_safe() { + int buffer[FooEnum::D] = { 0, 1, 2 }; + buffer[C] = 0; // no-warning +} + +void constant_enum_unsafe(FooEnum e) { + int buffer[FooEnum::D] = { 0, 1, 2 }; + buffer[e] = 0; // expected-warning{{unsafe buffer access}} +} + void constant_id_string(unsigned idx) { char safe_char = "abc"[1]; // no-warning safe_char = ""[0]; `````````` </details> https://github.com/llvm/llvm-project/pull/117370 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
