Remove Linkage::Private

This is the same as Linkage::Internal except that it doesn't emit any
symbol. Some backends may not support it and it isn't all that useful
anyway.

Author: bjorn3

src/base.rs

@@ -51,7 +51,6 @@ pub fn global_linkage_to_gcc(linkage: Linkage) -> GlobalKind {
         Linkage::WeakODR => unimplemented!(),
         Linkage::Appending => unimplemented!(),
         Linkage::Internal => GlobalKind::Internal,
-        Linkage::Private => GlobalKind::Internal,
         Linkage::ExternalWeak => GlobalKind::Imported, // TODO(antoyo): should be weak linkage.
         Linkage::Common => unimplemented!(),
     }
@@ -68,7 +67,6 @@ pub fn linkage_to_gcc(linkage: Linkage) -> FunctionType {
         Linkage::WeakODR => unimplemented!(),
         Linkage::Appending => unimplemented!(),
         Linkage::Internal => FunctionType::Internal,
-        Linkage::Private => FunctionType::Internal,
         Linkage::ExternalWeak => unimplemented!(),
         Linkage::Common => unimplemented!(),
     }

src/mono_item.rs

@@ -61,10 +61,7 @@ impl<'gcc, 'tcx> PreDefineCodegenMethods<'tcx> for CodegenCx<'gcc, 'tcx> {
         // compiler-rt, then we want to implicitly compile everything with hidden
         // visibility as we're going to link this object all over the place but
         // don't want the symbols to get exported.
-        if linkage != Linkage::Internal
-            && linkage != Linkage::Private
-            && self.tcx.is_compiler_builtins(LOCAL_CRATE)
-        {
+        if linkage != Linkage::Internal && self.tcx.is_compiler_builtins(LOCAL_CRATE) {
             #[cfg(feature = "master")]
             decl.add_attribute(FnAttribute::Visibility(gccjit::Visibility::Hidden));
         } else {