[all-commits] [llvm/llvm-project] 0c9c9d: [clang][Sema] Add truncation warning on fortified ...

[Takuya Shimizu via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 0c9c9dd9a24f9d715d950fef0ac7aae01437af96
      https://github.com/llvm/llvm-project/commit/0c9c9dd9a24f9d715d950fef0ac7aae01437af96
  Author: Takuya Shimizu <shimizu2486 at gmail.com>
  Date:   2023-08-26 (Sat, 26 Aug 2023)

  Changed paths:
    M clang/docs/ReleaseNotes.rst
    M clang/include/clang/Basic/DiagnosticSemaKinds.td
    M clang/lib/Sema/SemaChecking.cpp
    M clang/test/Analysis/taint-generic.c
    M clang/test/Sema/format-strings.c
    M clang/test/Sema/warn-fortify-source.c

  Log Message:
  -----------
  [clang][Sema] Add truncation warning on fortified snprintf

This patch warns on snprintf calls whose n argument is known to be smaller than the size of the formatted string like

```
char buf[5];
snprintf(buf, 5, "Hello");
```
This is a counterpart of gcc's Wformat-truncation
Fixes https://github.com/llvm/llvm-project/issues/64871

Reviewed By: aaron.ballman, nickdesaulniers
Differential Revision: https://reviews.llvm.org/D158562