[clang-format] Possible regression in clang-format-22?

[prj-]

I'm not sure which version is right, and which version is wrong. What do you think?

$ cat foo.c
static int foo(bool bar)
{
  return bar ? 0 : 1;
}
$ clang-format --style=file:clang-format.txt foo.c
static int foo(bool bar)
{
  return bar ? 0 : 1;
}
$ clang-format --version
clang-format version 21.1.0
$ clang-format-22 --style=file:clang-format.txt foo.c
static int foo(bool bar)
{ return bar ? 0 : 1; }
$ clang-format-22 --version
Debian clang-format version 22.0.0 (++20250908112350+a80c393a9c49-1~exp1~20250908112511.1692)

The faulty line is the first one from clang-format.txt, if it's commented out, then clang-format-22 formats the same as clang-format-21.

clang-format.txt

[llvmbot]

@llvm/issue-subscribers-clang-format

Author: Pierre Jolivet (prj-)

I'm not sure which version is right, and which version is wrong. What do you think? ```console $ cat foo.c static int foo(bool bar) { return bar ? 0 : 1; } $ clang-format --style=file:clang-format.txt foo.c static int foo(bool bar) { return bar ? 0 : 1; } $ clang-format --version clang-format version 21.1.0 $ clang-format-22 --style=file:clang-format.txt foo.c static int foo(bool bar) { return bar ? 0 : 1; } $ clang-format-22 --version Debian clang-format version 22.0.0 (++20250908112350+a80c393a9c49-1~exp1~20250908112511.1692) ``` The faulty line is the first one from `clang-format.txt`, if it's commented out, then `clang-format-22` formats the same as `clang-format-21`.

clang-format.txt

[owenca]

IMO version 22 is correct. See #151428. In your example, setting AllowShortBlocksOnASingleLine to Never or Empty will have desired format.

[prj-]

That's what I ended up doing (https://gitlab.com/petsc/petsc/-/commit/7a67c116a9680bb11dd92c3a4f53c28ae93b299a). The follow-up question is, shouldn't that be formatted as:

static int foo(bool bar) { return bar ? 0 : 1; }

[owenca]

No, because AllowShortFunctionsOnASingleLine overrides AllowShortBlocksOnASingleLine. In your case, only inline functions are merged:

static int foo(bool bar)
{
  return bar ? 0 : 1;
}

struct foo {
  void f() { return; }
};

[prj-]

OK, thanks. Feel free to close the issue then.