Index: lib/Target/X86/AsmParser/X86AsmParser.cpp
===================================================================
--- lib/Target/X86/AsmParser/X86AsmParser.cpp
+++ lib/Target/X86/AsmParser/X86AsmParser.cpp
@@ -1332,16 +1332,17 @@
   while (!Done) {
     bool UpdateLocLex = true;
 
+    AsmToken::TokenKind TK = getLexer().getKind();
     // The period in the dot operator (e.g., [ebx].foo.bar) is parsed as an
     // identifier.  Don't try an parse it as a register.
-    if (PrevTK != AsmToken::Error && Tok.getString().startswith("."))
+    if (PrevTK != AsmToken::Error && Tok.getString().startswith(".") &&
+        TK != AsmToken::Identifier)
       break;
 
     // If we're parsing an immediate expression, we don't expect a '['.
     if (SM.getStopOnLBrac() && getLexer().getKind() == AsmToken::LBrac)
       break;
 
-    AsmToken::TokenKind TK = getLexer().getKind();
     switch (TK) {
     default: {
       if (SM.isValidEndState()) {
Index: test/MC/X86/pr22004.s
===================================================================
--- test/MC/X86/pr22004.s
+++ test/MC/X86/pr22004.s
@@ -0,0 +1,3 @@
+// RUN: llvm-mc -triple x86_64-unknown-unknown -x86-asm-syntax=intel %s
+
+lea rax, qword ptr [rip + .L.str]