From d1a6d47f943d8df9d565de835babc1e2f3e8d45a Mon Sep 17 00:00:00 2001
From: Michael Woerister <michaelwoerister@posteo.net>
Date: Mon, 28 Nov 2016 17:44:51 -0500
Subject: [PATCH] Make LLVM symbol visibility FFI types more stable.

---
 src/librustc_llvm/ffi.rs      | 19 +++++++++-------
 src/librustc_trans/declare.rs |  2 +-
 src/rustllvm/RustWrapper.cpp  | 42 +++++++++++++++++++++++++++++++++++
 3 files changed, 54 insertions(+), 9 deletions(-)

diff --git a/src/librustc_llvm/ffi.rs b/src/librustc_llvm/ffi.rs
index b8f1540ad84..d2592a3acee 100644
--- a/src/librustc_llvm/ffi.rs
+++ b/src/librustc_llvm/ffi.rs
@@ -64,6 +64,15 @@ pub enum Linkage {
     CommonLinkage = 10,
 }
 
+// LLVMRustVisibility
+#[derive(Copy, Clone, PartialEq, Eq, Hash, Debug)]
+#[repr(C)]
+pub enum Visibility {
+    Default = 0,
+    Hidden = 1,
+    Protected = 2,
+}
+
 /// LLVMDiagnosticSeverity
 #[derive(Copy, Clone, Debug)]
 #[repr(C)]
@@ -399,13 +408,6 @@ pub type OperandBundleDefRef = *mut OperandBundleDef_opaque;
 pub type DiagnosticHandler = unsafe extern "C" fn(DiagnosticInfoRef, *mut c_void);
 pub type InlineAsmDiagHandler = unsafe extern "C" fn(SMDiagnosticRef, *const c_void, c_uint);
 
-/// LLVMVisibility
-#[repr(C)]
-pub enum Visibility {
-    Default,
-    Hidden,
-    Protected,
-}
 
 pub mod debuginfo {
     use super::MetadataRef;
@@ -655,7 +657,8 @@ extern "C" {
     pub fn LLVMRustSetLinkage(Global: ValueRef, RustLinkage: Linkage);
     pub fn LLVMGetSection(Global: ValueRef) -> *const c_char;
     pub fn LLVMSetSection(Global: ValueRef, Section: *const c_char);
-    pub fn LLVMSetVisibility(Global: ValueRef, Viz: Visibility);
+    pub fn LLVMRustGetVisibility(Global: ValueRef) -> Visibility;
+    pub fn LLVMRustSetVisibility(Global: ValueRef, Viz: Visibility);
     pub fn LLVMGetAlignment(Global: ValueRef) -> c_uint;
     pub fn LLVMSetAlignment(Global: ValueRef, Bytes: c_uint);
     pub fn LLVMSetDLLStorageClass(V: ValueRef, C: DLLStorageClass);
diff --git a/src/librustc_trans/declare.rs b/src/librustc_trans/declare.rs
index 7d6a672077a..eef3b9b1147 100644
--- a/src/librustc_trans/declare.rs
+++ b/src/librustc_trans/declare.rs
@@ -78,7 +78,7 @@ fn declare_raw_fn(ccx: &CrateContext, name: &str, callconv: llvm::CallConv, ty:
     // don't want the symbols to get exported.
     if attr::contains_name(ccx.tcx().map.krate_attrs(), "compiler_builtins") {
         unsafe {
-            llvm::LLVMSetVisibility(llfn, llvm::Visibility::Hidden);
+            llvm::LLVMRustSetVisibility(llfn, llvm::Visibility::Hidden);
         }
     }
 
diff --git a/src/rustllvm/RustWrapper.cpp b/src/rustllvm/RustWrapper.cpp
index 51859a928c4..6a95b65d5e9 100644
--- a/src/rustllvm/RustWrapper.cpp
+++ b/src/rustllvm/RustWrapper.cpp
@@ -1408,3 +1408,45 @@ extern "C" void LLVMRustSetLinkage(LLVMValueRef V, LLVMRustLinkage RustLinkage)
 extern "C" LLVMContextRef LLVMRustGetValueContext(LLVMValueRef V) {
     return wrap(&unwrap(V)->getContext());
 }
+
+enum class LLVMRustVisibility {
+    Default = 0,
+    Hidden = 1,
+    Protected = 2,
+};
+
+static LLVMRustVisibility to_rust(LLVMVisibility vis) {
+    switch (vis) {
+        case LLVMDefaultVisibility:
+            return LLVMRustVisibility::Default;
+        case LLVMHiddenVisibility:
+            return LLVMRustVisibility::Hidden;
+        case LLVMProtectedVisibility:
+            return LLVMRustVisibility::Protected;
+
+        default:
+            llvm_unreachable("Invalid LLVMRustVisibility value!");
+    }
+}
+
+static LLVMVisibility from_rust(LLVMRustVisibility vis) {
+    switch (vis) {
+        case LLVMRustVisibility::Default:
+            return LLVMDefaultVisibility;
+        case LLVMRustVisibility::Hidden:
+            return LLVMHiddenVisibility;
+        case LLVMRustVisibility::Protected:
+            return LLVMProtectedVisibility;
+
+        default:
+            llvm_unreachable("Invalid LLVMRustVisibility value!");
+    }
+}
+
+extern "C" LLVMRustVisibility LLVMRustGetVisibility(LLVMValueRef V) {
+    return to_rust(LLVMGetVisibility(V));
+}
+
+extern "C" void LLVMRustSetVisibility(LLVMValueRef V, LLVMRustVisibility RustVisibility) {
+    LLVMSetVisibility(V, from_rust(RustVisibility));
+}