[all-commits] [llvm/llvm-project] 55a51e: Disallow an empty string literal in an asm label

[AaronBallman via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 55a51e1c79a21080289ba88d5eac4bbe54ec4272
      https://github.com/llvm/llvm-project/commit/55a51e1c79a21080289ba88d5eac4bbe54ec4272
  Author: Aaron Ballman <aaron at aaronballman.com>
  Date:   2020-01-08 (Wed, 08 Jan 2020)

  Changed paths:
    M clang/include/clang/Basic/DiagnosticParseKinds.td
    M clang/include/clang/Parse/Parser.h
    M clang/lib/Parse/ParseDecl.cpp
    M clang/lib/Parse/ParseDeclCXX.cpp
    M clang/lib/Parse/ParseExprCXX.cpp
    M clang/lib/Parse/ParseStmtAsm.cpp
    M clang/lib/Parse/Parser.cpp
    M clang/test/AST/ast-print-attr.c
    M clang/test/CodeGen/asm-label.c
    M clang/test/Parser/asm.c

  Log Message:
  -----------
  Disallow an empty string literal in an asm label

An empty string literal in an asm label does not make a whole lot of sense. GCC
does not diagnose such a construct, but it also generates code that cannot be
assembled by gas should two symbols have an empty asm label within the same TU.
This does not affect an asm statement with an empty string literal, which is
still a useful construct.