[clang-format] Add new style option IndentGotoLabels

Summary:
This option determines whether goto labels are indented according to scope. Setting this option to false causes goto labels to be flushed to the left.
This is mostly copied from [[ http://lists.llvm.org/pipermail/cfe-dev/2015-September/045014.html | this patch ]] submitted by Christian Neukirchen that didn't make its way into trunk.

```
     true:                                  false:
     int f() {                      vs.     int f() {
       if (foo()) {                           if (foo()) {
       label1:                              label1:
         bar();                                 bar();
       }                                      }
     label2:                                label2:
       return 1;                              return 1;
     }                                      }
```

Reviewers: klimek, MyDeveloperDay

Reviewed By: MyDeveloperDay

Subscribers: cfe-commits

Tags: #clang, #clang-tools-extra

Patch by: tetsuo-cpp

Differential Revision: https://reviews.llvm.org/D67037

llvm-svn: 371719

1 files changed, 2 insertions, 0 deletions

diff --git a/clang/lib/Format/Format.cpp b/clang/lib/Format/Format.cpp
index 90745b6e0a6..81fdab4ed70 100644
--- a/clang/lib/Format/Format.cpp
+++ b/clang/lib/Format/Format.cpp
@@ -453,6 +453,7 @@ template <> struct MappingTraits<FormatStyle> {
     IO.mapOptional("IncludeCategories", Style.IncludeStyle.IncludeCategories);
     IO.mapOptional("IncludeIsMainRegex", Style.IncludeStyle.IncludeIsMainRegex);
     IO.mapOptional("IndentCaseLabels", Style.IndentCaseLabels);
+    IO.mapOptional("IndentGotoLabels", Style.IndentGotoLabels);
     IO.mapOptional("IndentPPDirectives", Style.IndentPPDirectives);
     IO.mapOptional("IndentWidth", Style.IndentWidth);
     IO.mapOptional("IndentWrappedFunctionNames",
@@ -725,6 +726,7 @@ FormatStyle getLLVMStyle(FormatStyle::LanguageKind Language) {
   LLVMStyle.IncludeStyle.IncludeIsMainRegex = "(Test)?$";
   LLVMStyle.IncludeStyle.IncludeBlocks = tooling::IncludeStyle::IBS_Preserve;
   LLVMStyle.IndentCaseLabels = false;
+  LLVMStyle.IndentGotoLabels = true;
   LLVMStyle.IndentPPDirectives = FormatStyle::PPDIS_None;
   LLVMStyle.IndentWrappedFunctionNames = false;
   LLVMStyle.IndentWidth = 2;