[Tooling] Correct the "-std" compile command option.

Summary:
"-std c++11" is not valid in compiler, we have to use "-std=c++11".

Test in vscode with this patch, code completion for header works as expected.

Reviewers: sammccall

Subscribers: cfe-commits, klimek

Differential Revision: https://reviews.llvm.org/D45512

llvm-svn: 329786

1 files changed, 2 insertions, 2 deletions

diff --git a/clang/lib/Tooling/InterpolatingCompilationDatabase.cpp b/clang/lib/Tooling/InterpolatingCompilationDatabase.cpp
index cf29744f307..bc564584bd0 100644
--- a/clang/lib/Tooling/InterpolatingCompilationDatabase.cpp
+++ b/clang/lib/Tooling/InterpolatingCompilationDatabase.cpp
@@ -191,9 +191,9 @@ struct TransferableCommand {
     // --std flag may only be transferred if the language is the same.
     // We may consider "translating" these, e.g. c++11 -> c11.
     if (Std != LangStandard::lang_unspecified && foldType(TargetType) == Type) {
-      Result.CommandLine.push_back("-std");
       Result.CommandLine.push_back(
-          LangStandard::getLangStandardForKind(Std).getName());
+          "-std=" +
+          std::string(LangStandard::getLangStandardForKind(Std).getName()));
     }
     Result.CommandLine.push_back(Filename);
     return Result;