2 files changed, 15 insertions, 1 deletions
diff --git a/llvm/lib/Target/ARM/ARMAsmPrinter.cpp b/llvm/lib/Target/ARM/ARMAsmPrinter.cpp
index 0300f5875ca..b17d4aa19f7 100644
--- a/llvm/lib/Target/ARM/ARMAsmPrinter.cpp
+++ b/llvm/lib/Target/ARM/ARMAsmPrinter.cpp
@@ -629,6 +629,8 @@ void ARMAsmPrinter::emitAttributes() {
   MCTargetStreamer &TS = *OutStreamer.getTargetStreamer();
   ARMTargetStreamer &ATS = static_cast<ARMTargetStreamer &>(TS);
 
+  ATS.emitTextAttribute(ARMBuildAttrs::conformance, "2.09");
+
   ATS.switchVendor("aeabi");
 
   std::string CPUString = Subtarget->getCPUString();
diff --git a/llvm/lib/Target/ARM/MCTargetDesc/ARMELFStreamer.cpp b/llvm/lib/Target/ARM/MCTargetDesc/ARMELFStreamer.cpp
index e92a43c5b79..f9403063dd6 100644
--- a/llvm/lib/Target/ARM/MCTargetDesc/ARMELFStreamer.cpp
+++ b/llvm/lib/Target/ARM/MCTargetDesc/ARMELFStreamer.cpp
@@ -300,7 +300,19 @@ private:
     StringRef StringValue;
 
     static bool LessTag(const AttributeItem &LHS, const AttributeItem &RHS) {
-      return (LHS.Tag < RHS.Tag);
+      // The conformance tag must be emitted first when serialised
+      // into an object file. Specifically, the addenda to the ARM ABI
+      // states that (2.3.7.4):
+      //
+      // "To simplify recognition by consumers in the common case of
+      // claiming conformity for the whole file, this tag should be
+      // emitted first in a file-scope sub-subsection of the first
+      // public subsection of the attributes section."
+      //
+      // So it is special-cased in this comparison predicate when the
+      // attributes are sorted in finishAttributeSection().
+      return (RHS.Tag != ARMBuildAttrs::conformance) &&
+             ((LHS.Tag == ARMBuildAttrs::conformance) || (LHS.Tag < RHS.Tag));
     }
   };