diff --git a/llvm/lib/DebugInfo/Symbolize/Symbolize.cpp b/llvm/lib/DebugInfo/Symbolize/Symbolize.cpp
--- a/llvm/lib/DebugInfo/Symbolize/Symbolize.cpp
+++ b/llvm/lib/DebugInfo/Symbolize/Symbolize.cpp
@@ -665,6 +665,15 @@
     return Result;
   }
 
+  if (Name.size() >= 2 && Name[0] == '_' && Name[1] == 'R') {
+    char *DemangledName = rustDemangle(Name.c_str(), nullptr, nullptr, nullptr);
+    if (DemangledName == nullptr)
+      return Name;
+    std::string Result = DemangledName;
+    free(DemangledName);
+    return Result;
+  }
+
   if (!Name.empty() && Name.front() == '?') {
     // Only do MSVC C++ demangling on symbols starting with '?'.
     int status = 0;
diff --git a/llvm/test/DebugInfo/symbolize-demangling.s b/llvm/test/DebugInfo/symbolize-demangling.s
--- a/llvm/test/DebugInfo/symbolize-demangling.s
+++ b/llvm/test/DebugInfo/symbolize-demangling.s
@@ -2,23 +2,29 @@
 
 # RUN: llvm-mc --filetype=obj --triple=x86_64-pc-linux %s -o %t.o -g
 
-# RUN: llvm-symbolizer --obj=%t.o 0 1 2 | FileCheck %s
+# RUN: llvm-symbolizer --obj=%t.o 0 1 2 3 | FileCheck %s
 
 # CHECK:       f()
-# CHECK-NEXT:  symbolize-demangling.s:20
+# CHECK-NEXT:  symbolize-demangling.s:24
 # CHECK-EMPTY:
 # CHECK-NEXT:  {{^g$}}
-# CHECK-NEXT:  symbolize-demangling.s:22
+# CHECK-NEXT:  symbolize-demangling.s:26
 # CHECK-EMPTY:
 # CHECK-NEXT:  {{^baz$}}
-# CHECK-NEXT:  symbolize-demangling.s:24
+# CHECK-NEXT:  symbolize-demangling.s:28
+# CHECK-EMPTY:
+# CHECK-NEXT:  {{^x::y$}}
+# CHECK-NEXT:  symbolize-demangling.s:30
 
 .type _Z1fv,@function
 .type g,@function
 .type baz,@function
+.type _RNvC1x1y,@function
 _Z1fv:
   nop
 g:
   nop
 baz:
   nop
+_RNvC1x1y:
+  nop