Fix another LoopConvert fail.

Summary: Prevent LoopConvert from taking as alias anything that comes from a random member function call.

Reviewers: alexfh

Subscribers: klimek, cfe-commits

Differential Revision: http://reviews.llvm.org/D12370

llvm-svn: 246039

2 files changed, 15 insertions, 3 deletions

diff --git a/clang-tools-extra/clang-tidy/modernize/LoopConvertUtils.cpp b/clang-tools-extra/clang-tidy/modernize/LoopConvertUtils.cpp
index 0058ea6ba60..ace0aee3114 100644
--- a/clang-tools-extra/clang-tidy/modernize/LoopConvertUtils.cpp
+++ b/clang-tools-extra/clang-tidy/modernize/LoopConvertUtils.cpp
@@ -368,8 +368,14 @@ static bool isAliasDecl(const Decl *TheDecl, const VarDecl *IndexVar) {
     break;
   }
 
-  case Stmt::CXXMemberCallExprClass:
-    return true;
+  case Stmt::CXXMemberCallExprClass: {
+    const auto *MemCall = cast<CXXMemberCallExpr>(Init);
+    if (MemCall->getMethodDecl()->getName() == "at") {
+      assert(MemCall->getNumArgs() == 1);
+      return isIndexInSubscriptExpr(MemCall->getArg(0), IndexVar);
+    }
+    return false;
+  }
 
   default:
     break;
diff --git a/clang-tools-extra/test/clang-tidy/modernize-loop-convert-extra.cpp b/clang-tools-extra/test/clang-tidy/modernize-loop-convert-extra.cpp
index 85711b6e560..4095d1057dd 100644
--- a/clang-tools-extra/test/clang-tidy/modernize-loop-convert-extra.cpp
+++ b/clang-tools-extra/test/clang-tidy/modernize-loop-convert-extra.cpp
@@ -207,11 +207,17 @@ void refs_and_vals() {
   for (dependent<int>::iterator it = dep.begin(), e = dep.end(); it != e; ++it) {
     printf("%d\n", *it);
     const int& idx = other[0];
+    unsigned othersize = other.size();
   }
-  // CHECK-MESSAGES: :[[@LINE-4]]:3: warning: use range-based for loop instead
+  // CHECK-MESSAGES: :[[@LINE-5]]:3: warning: use range-based for loop instead
   // CHECK-FIXES: for (auto & elem : dep)
   // CHECK-FIXES-NEXT: printf("%d\n", elem);
   // CHECK-FIXES-NEXT: const int& idx = other[0];
+  // CHECK-FIXES-NEXT: unsigned othersize = other.size();
+
+  for (int i = 0, e = dep.size(); i != e; ++i) {
+    int idx = other.at(i);
+  }
 }
 
 } // namespace NamingAlias