From b63bfa45b621745f9d6e401ad84630d6f465bc79 Mon Sep 17 00:00:00 2001
From: Shoaib Meenai <smeenai@fb.com>
Date: Wed, 16 Oct 2024 20:57:49 -0700
Subject: [PATCH] [CIR][CIRGen] Ensure default visibility for local linkage
 functions

LLVM's verifier enforces this, which was previously causing us to fail
verification. This is a bit of a band-aid; the overall linkage and
visibility setting flow needs some work to match the original.
---
 clang/lib/CIR/CodeGen/CIRGenModule.cpp        | 11 +++++++++--
 clang/test/CIR/CodeGen/visibility-attribute.c | 15 +++++++++++++++
 2 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/clang/lib/CIR/CodeGen/CIRGenModule.cpp b/clang/lib/CIR/CodeGen/CIRGenModule.cpp
index cb96adf1e257..872e5e9e05c5 100644
--- a/clang/lib/CIR/CodeGen/CIRGenModule.cpp
+++ b/clang/lib/CIR/CodeGen/CIRGenModule.cpp
@@ -2608,8 +2608,15 @@ void CIRGenModule::setFunctionAttributes(GlobalDecl globalDecl,
 
   // TODO(cir): Complete the remaining part of the function.
   assert(!MissingFeatures::setFunctionAttributes());
-  auto decl = globalDecl.getDecl();
-  func.setGlobalVisibilityAttr(getGlobalVisibilityAttrFromDecl(decl));
+
+  // TODO(cir): This needs a lot of work to better match CodeGen. That
+  // ultimately ends up in setGlobalVisibility, which already has the linkage of
+  // the LLVM GV (corresponding to our FuncOp) computed, so it doesn't have to
+  // recompute it here. This is a minimal fix for now.
+  if (!isLocalLinkage(getFunctionLinkage(globalDecl))) {
+    auto decl = globalDecl.getDecl();
+    func.setGlobalVisibilityAttr(getGlobalVisibilityAttrFromDecl(decl));
+  }
 }
 
 /// If the specified mangled name is not in the module,
diff --git a/clang/test/CIR/CodeGen/visibility-attribute.c b/clang/test/CIR/CodeGen/visibility-attribute.c
index fb675fb51751..07834d78910e 100644
--- a/clang/test/CIR/CodeGen/visibility-attribute.c
+++ b/clang/test/CIR/CodeGen/visibility-attribute.c
@@ -30,9 +30,24 @@ void __attribute__((__visibility__("protected"))) foo_protected();
 // CIR: cir.func no_proto private protected @foo_protected(...)
 // LLVM: declare {{.*}} protected void @foo_protected(...)
 
+static void static_foo_default() {}
+// CIR: cir.func no_proto internal private @static_foo_default()
+// LLVM: define internal void @static_foo_default()
+
+static void __attribute__((__visibility__("hidden"))) static_foo_hidden() {}
+// CIR: cir.func no_proto internal private @static_foo_hidden()
+// LLVM: define internal void @static_foo_hidden()
+
+static void __attribute__((__visibility__("protected"))) static_foo_protected() {}
+// CIR: cir.func no_proto internal private @static_foo_protected()
+// LLVM: define internal void @static_foo_protected()
+
 void call_foo()
 {
   foo_default();
   foo_hidden();
   foo_protected();
+  static_foo_default();
+  static_foo_hidden();
+  static_foo_protected();
 }