[clang-format] Non-zero exit code when formatted correctly.

[sridhargopinath]

Below is a sample commit to showcase the bug. There are two lines added that conform to clang-format formatting.

diff --git a/llvm/lib/IR/Instructions.cpp b/llvm/lib/IR/Instructions.cpp
index f5039eb5126c..0e3f24fe4aa9 100644
--- a/llvm/lib/IR/Instructions.cpp
+++ b/llvm/lib/IR/Instructions.cpp
@@ -1647,6 +1647,8 @@ void AtomicRMWInst::Init(BinOp Operation, Value *Ptr, Value *Val,
          "Ptr must be a pointer to Val type!");
   assert(Ordering != AtomicOrdering::NotAtomic &&
          "AtomicRMW instructions must be atomic!");
+  assert(Ordering != AtomicOrdering::NotAtomic &&
+         "AtomicRMW instructions must be atomic!");
 }
 
 AtomicRMWInst::AtomicRMWInst(BinOp Operation, Value *Ptr, Value *Val,

Running clang-format on the commit does not show any formatting changes. However, it returns non-zero exit code.

➜ clang/tools/clang-format/git-clang-format -v --binary /path/to/clang-format --diff HEAD~1 HEAD
Running clang-format on the following files:
    llvm/lib/IR/Instructions.cpp
old tree: HEAD
new tree: 98edebbef1ca81ada0b968a3c0d65bbb6920cd59

➜ echo $?            
1

[sridhargopinath]

More discussion here: https://reviews.llvm.org/D129311

Currently, the exit code is zero when there are no code changes to check. However, the exit code needs to be zero even when there are code changes that conforms to clang's formatting.

[llvmbot]

@llvm/issue-subscribers-clang-format