From 044b71a30fa873952931341159c3773f23937868 Mon Sep 17 00:00:00 2001
From: Kaelyn Uhrain <rikka@google.com>
Date: Fri, 28 Feb 2014 18:12:42 +0000
Subject: [PATCH] Don't suggest non-static methods as corrections when they
 obviously won't work (i.e. when not doing a member lookup and not in a method
 from the same class or a descendant class).

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@202520 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/clang/Sema/TypoCorrection.h  |  5 ++++-
 lib/Sema/SemaLookup.cpp              | 32 +++++++++++++++++++++++-----
 lib/Sema/SemaOverload.cpp            |  2 +-
 test/SemaCXX/typo-correction-pt2.cpp |  9 ++++++++
 4 files changed, 41 insertions(+), 7 deletions(-)

diff --git a/include/clang/Sema/TypoCorrection.h b/include/clang/Sema/TypoCorrection.h
index f0b7726498..c28720b2b1 100644
--- a/include/clang/Sema/TypoCorrection.h
+++ b/include/clang/Sema/TypoCorrection.h
@@ -305,13 +305,16 @@ public:
 class FunctionCallFilterCCC : public CorrectionCandidateCallback {
 public:
   FunctionCallFilterCCC(Sema &SemaRef, unsigned NumArgs,
-                        bool HasExplicitTemplateArgs);
+                        bool HasExplicitTemplateArgs,
+                        bool AllowNonStaticMethods = true);
 
   virtual bool ValidateCandidate(const TypoCorrection &candidate);
 
  private:
   unsigned NumArgs;
   bool HasExplicitTemplateArgs;
+  bool AllowNonStaticMethods;
+  DeclContext *CurContext;
 };
 
 // @brief Callback class that effectively disabled typo correction
diff --git a/lib/Sema/SemaLookup.cpp b/lib/Sema/SemaLookup.cpp
index 1a47340d69..5df0a43621 100644
--- a/lib/Sema/SemaLookup.cpp
+++ b/lib/Sema/SemaLookup.cpp
@@ -4546,8 +4546,11 @@ bool CorrectionCandidateCallback::ValidateCandidate(const TypoCorrection &candid
 }
 
 FunctionCallFilterCCC::FunctionCallFilterCCC(Sema &SemaRef, unsigned NumArgs,
-                                             bool HasExplicitTemplateArgs)
-    : NumArgs(NumArgs), HasExplicitTemplateArgs(HasExplicitTemplateArgs) {
+                                             bool HasExplicitTemplateArgs,
+                                             bool AllowNonStaticMethods)
+    : NumArgs(NumArgs), HasExplicitTemplateArgs(HasExplicitTemplateArgs),
+      AllowNonStaticMethods(AllowNonStaticMethods),
+      CurContext(SemaRef.CurContext) {
   WantTypeSpecifiers = SemaRef.getLangOpts().CPlusPlus;
   WantRemainingKeywords = false;
 }
@@ -4576,9 +4579,28 @@ bool FunctionCallFilterCCC::ValidateCandidate(const TypoCorrection &candidate) {
             return true;
       }
     }
-    if (FD && FD->getNumParams() >= NumArgs &&
-        FD->getMinRequiredArguments() <= NumArgs)
-      return true;
+
+    // Skip the current candidate if it is not a FunctionDecl or does not accept
+    // the current number of arguments.
+    if (!FD || !(FD->getNumParams() >= NumArgs &&
+                 FD->getMinRequiredArguments() <= NumArgs))
+      continue;
+
+    // If the current candidate is a non-static C++ method and non-static
+    // methods are being excluded, then skip the candidate unless the current
+    // DeclContext is a method in the same class or a descendent class of the
+    // candidate's parent class.
+    if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
+      if (!AllowNonStaticMethods && !MD->isStatic()) {
+        CXXMethodDecl *CurMD = dyn_cast_or_null<CXXMethodDecl>(CurContext);
+        CXXRecordDecl *CurRD =
+            CurMD ? CurMD->getParent()->getCanonicalDecl() : 0;
+        CXXRecordDecl *RD = MD->getParent()->getCanonicalDecl();
+        if (!CurRD || (CurRD != RD && !CurRD->isDerivedFrom(RD)))
+          continue;
+      }
+    }
+    return true;
   }
   return false;
 }
diff --git a/lib/Sema/SemaOverload.cpp b/lib/Sema/SemaOverload.cpp
index fb77ba616f..eaf3d35148 100644
--- a/lib/Sema/SemaOverload.cpp
+++ b/lib/Sema/SemaOverload.cpp
@@ -10385,7 +10385,7 @@ BuildRecoveryCallExpr(Sema &SemaRef, Scope *S, Expr *Fn,
   LookupResult R(SemaRef, ULE->getName(), ULE->getNameLoc(),
                  Sema::LookupOrdinaryName);
   FunctionCallFilterCCC Validator(SemaRef, Args.size(),
-                                  ExplicitTemplateArgs != 0);
+                                  ExplicitTemplateArgs != 0, false);
   NoTypoCorrectionCCC RejectAll;
   CorrectionCandidateCallback *CCC = AllowTypoCorrection ?
       (CorrectionCandidateCallback*)&Validator :
diff --git a/test/SemaCXX/typo-correction-pt2.cpp b/test/SemaCXX/typo-correction-pt2.cpp
index e08bef0741..e39a24bd09 100644
--- a/test/SemaCXX/typo-correction-pt2.cpp
+++ b/test/SemaCXX/typo-correction-pt2.cpp
@@ -234,3 +234,12 @@ class Baz {
                      // expected-error {{expected member name or ';' after declaration specifiers}}
 };
 }
+
+namespace PR18852 {
+void func() {
+  struct foo {
+    void bar() {}
+  };
+  bar();  // expected-error-re {{use of undeclared identifier 'bar'{{$}}}}
+}
+}
-- 
2.40.0