[all-commits] [llvm/llvm-project] dd0f64: [Sema] Add check for bitfield assignments to large...

[vabridgers via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: dd0f642e6ec5049ccabe3f462cc427ffe213829b
      https://github.com/llvm/llvm-project/commit/dd0f642e6ec5049ccabe3f462cc427ffe213829b
  Author: vabridgers <58314289+vabridgers at users.noreply.github.com>
  Date:   2023-10-12 (Thu, 12 Oct 2023)

  Changed paths:
    M clang/docs/ReleaseNotes.rst
    M clang/include/clang/Basic/DiagnosticGroups.td
    M clang/include/clang/Basic/DiagnosticSemaKinds.td
    M clang/lib/Sema/SemaChecking.cpp
    A clang/test/SemaCXX/bitfield-width.c

  Log Message:
  -----------
  [Sema] Add check for bitfield assignments to larger integral types (#68276)

We noticed that clang does not check for bitfield assignment widths,
while gcc does check this.

gcc produced a warning like so for it's -Wconversion flag:
```
$ gcc -Wconversion -c test.c
test.c: In function 'foo':
test.c:10:15: warning: conversion from 'int' to 'signed char:7' may change value [-Wconversion]
   10 |      vxx.bf = x; // no warning
      |               ^
```

This change simply adds this check for integral types under the
-Wbitfield-conversion compiler option.