Convert unreachable return statement into llvm_unreachable

[shafik]

Static analysis flags the final return statement in ReadExtensionBlock as unreachable and indeed it is since there is no way to exit the while(true) loop besides a return statement.

So I am converting it into a llvm_unreachable to explicitly document this.

[llvmbot]

@llvm/pr-subscribers-clang-modules

@llvm/pr-subscribers-clang

Author: Shafik Yaghmour (shafik)

Changes

Static analysis flags the final return statement in ReadExtensionBlock as unreachable and indeed it is since there is no way to exit the while(true) loop besides a return statement.

So I am converting it into a llvm_unreachable to explicitly document this.

---

Full diff: https://github.com/llvm/llvm-project/pull/129627.diff

1 Files Affected:

• (modified) clang/lib/Serialization/ASTReader.cpp (+1-1)

diff --git a/clang/lib/Serialization/ASTReader.cpp b/clang/lib/Serialization/ASTReader.cpp
index ea4b233a6c573..ca09c3d79d941 100644
--- a/clang/lib/Serialization/ASTReader.cpp
+++ b/clang/lib/Serialization/ASTReader.cpp
@@ -5329,7 +5329,7 @@ llvm::Error ASTReader::ReadExtensionBlock(ModuleFile &F) {
     }
   }
 
-  return llvm::Error::success();
+  llvm_unreachable("ReadExtensionBlock should return from while loop");
 }
 
 void ASTReader::InitializeContext() {

[tahonermann]

Looks good to me.

[AaronBallman]

LGTM!