diff --git a/llvm/lib/Target/X86/AsmParser/X86AsmParser.cpp b/llvm/lib/Target/X86/AsmParser/X86AsmParser.cpp
index d102b371d4aebfd82b18480727d11de31c663101..e5f23e018bf3db7e91f3de8f766067971956b291 100644
--- a/llvm/lib/Target/X86/AsmParser/X86AsmParser.cpp
+++ b/llvm/lib/Target/X86/AsmParser/X86AsmParser.cpp
@@ -231,6 +231,7 @@ struct X86Operand {
 
 bool X86ATTAsmParser::ParseRegister(X86Operand &Op) {
   const AsmToken &TokPercent = getLexer().getTok();
+  (void)TokPercent; // Avoid warning when assertions are disabled.
   assert(TokPercent.is(AsmToken::Percent) && "Invalid token kind!");
   getLexer().Lex(); // Eat percent token.