[AsmParser] Return an error in the case of empty symbol ref in an expression

The following instruction:

> str q28, [x0, #1*6*4*@]

contains a @ which is parsed as an empty symbol. The parser returns true
but has no error, so the assembler continues by ignoring the
instruction.

Differential Revision: https://reviews.llvm.org/D52645

llvm-svn: 343961

1 files changed, 1 insertions, 1 deletions

diff --git a/llvm/lib/MC/MCParser/AsmParser.cpp b/llvm/lib/MC/MCParser/AsmParser.cpp
index eb76dd07088..6eb7fd0d0b6 100644
--- a/llvm/lib/MC/MCParser/AsmParser.cpp
+++ b/llvm/lib/MC/MCParser/AsmParser.cpp
@@ -1103,7 +1103,7 @@ bool AsmParser::parsePrimaryExpr(const MCExpr *&Res, SMLoc &EndLoc) {
     // This is a symbol reference.
     StringRef SymbolName = Identifier;
     if (SymbolName.empty())
-      return true;
+      return Error(getLexer().getLoc(), "expected a symbol reference");
 
     MCSymbolRefExpr::VariantKind Variant = MCSymbolRefExpr::VK_None;