From e1854817e5b8814ad7776a1839c57392596f74e0 Mon Sep 17 00:00:00 2001
From: Daniel Kolsoi <thadan64@gmail.com>
Date: Sat, 20 Oct 2018 12:55:03 -0400
Subject: [PATCH] Forgot to commit comdat.rs

---
 src/comdat.rs | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 50 insertions(+)
 create mode 100644 src/comdat.rs

diff --git a/src/comdat.rs b/src/comdat.rs
new file mode 100644
index 00000000000..ecc93606c2e
--- /dev/null
+++ b/src/comdat.rs
@@ -0,0 +1,50 @@
+//! A `Comdat` helps resolve linker errors for duplicate sections.
+// https://llvm.org/doxygen/IR_2Comdat_8h_source.html
+// https://stackoverflow.com/questions/1834597/what-is-the-comdat-section-used-for
+
+use llvm_sys::comdat::{LLVMComdatSelectionKind, LLVMSetComdatSelectionKind, LLVMGetComdatSelectionKind};
+use llvm_sys::prelude::LLVMComdatRef;
+
+enum_rename!{
+    /// Determines how linker conflicts are to be resolved.
+    ComdatSelectionKind <=> LLVMComdatSelectionKind {
+        /// The linker may choose any COMDAT.
+        Any <=> LLVMAnyComdatSelectionKind,
+        /// The data referenced by the COMDAT must be the same.
+        ExactMatch <=> LLVMExactMatchComdatSelectionKind,
+        /// The linker will choose the largest COMDAT.
+        Largest <=> LLVMLargestComdatSelectionKind,
+        /// No other Module may specify this COMDAT.
+        NoDuplicates <=> LLVMNoDuplicatesComdatSelectionKind,
+        /// The data referenced by the COMDAT must be the same size.
+        SameSize <=> LLVMSameSizeComdatSelectionKind,
+    }
+}
+
+/// A `Comdat` determines how to resolve duplicate sections when linking.
+#[derive(Debug, PartialEq, Copy, Clone)]
+pub struct Comdat(pub(crate) LLVMComdatRef);
+
+impl Comdat {
+    pub(crate) fn new(comdat: LLVMComdatRef) -> Self {
+        debug_assert!(!comdat.is_null());
+
+        Comdat(comdat)
+    }
+
+    /// Gets what kind of `Comdat` this is.
+    pub fn get_selection_kind(&self) -> ComdatSelectionKind {
+        let kind_ptr = unsafe {
+            LLVMGetComdatSelectionKind(self.0)
+        };
+
+        ComdatSelectionKind::new(kind_ptr)
+    }
+
+    /// Sets what kind of `Comdat` this should be.
+    pub fn set_selection_kind(&self, kind: ComdatSelectionKind) {
+        unsafe {
+            LLVMSetComdatSelectionKind(self.0, kind.as_llvm_enum())
+        }
+    }
+}