[clang-tools-extra] r345882 - Fix clang -Wimplicit-fallthrough warnings across llvm, NFC

[Reid Kleckner via cfe-commits]

Author: rnk
Date: Thu Nov  1 12:54:45 2018
New Revision: 345882

URL: http://llvm.org/viewvc/llvm-project?rev=345882&view=rev
Log:
Fix clang -Wimplicit-fallthrough warnings across llvm, NFC

This patch should not introduce any behavior changes. It consists of
mostly one of two changes:
1. Replacing fall through comments with the LLVM_FALLTHROUGH macro
2. Inserting 'break' before falling through into a case block consisting
   of only 'break'.

We were already using this warning with GCC, but its warning behaves
slightly differently. In this patch, the following differences are
relevant:
1. GCC recognizes comments that say "fall through" as annotations, clang
   doesn't
2. GCC doesn't warn on "case N: foo(); default: break;", clang does
3. GCC doesn't warn when the case contains a switch, but falls through
   the outer case.

I will enable the warning separately in a follow-up patch so that it can
be cleanly reverted if necessary.

Reviewers: alexfh, rsmith, lattner, rtrieu, EricWF, bollu

Differential Revision: https://reviews.llvm.org/D53950

Modified:
    clang-tools-extra/trunk/clang-tidy/google/AvoidCStyleCastsCheck.cpp

Modified: clang-tools-extra/trunk/clang-tidy/google/AvoidCStyleCastsCheck.cpp
URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clang-tidy/google/AvoidCStyleCastsCheck.cpp?rev=345882&r1=345881&r2=345882&view=diff
==============================================================================
--- clang-tools-extra/trunk/clang-tidy/google/AvoidCStyleCastsCheck.cpp (original)
+++ clang-tools-extra/trunk/clang-tidy/google/AvoidCStyleCastsCheck.cpp Thu Nov  1 12:54:45 2018
@@ -187,7 +187,7 @@ void AvoidCStyleCastsCheck::check(const
       }
       break;
     }
-  // FALLTHROUGH
+    LLVM_FALLTHROUGH;
   case clang::CK_IntegralCast:
     // Convert integral and no-op casts between builtin types and enums to
     // static_cast. A cast from enum to integer may be unnecessary, but it's