Place implictly declared functions at block scope

Such implicitly declared functions behave as if the enclosing block
contained the declaration extern int name() (C90, 6.3.3.2 Function calls),
thus their names should have block scope (C90, 6.1.2.1 Scope of identifiers).

This patch fixes https://bugs.llvm.org/show_bug.cgi?id=33224

Differential Revision: https://reviews.llvm.org/D33676

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@310616 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/clang/Sema/Scope.h b/include/clang/Sema/Scope.h
index d0b006b82ec6e310fad57b67f50e6fca8dcbf28e..e892d8205b557feb0971c0459d0c5a41e29aa0d5 100644 (file)
--- a/include/clang/Sema/Scope.h
+++ b/include/clang/Sema/Scope.h
@@ -124,6 +124,9 @@ public:
 
     /// We are currently in the filter expression of an SEH except block.
     SEHFilterScope = 0x200000,
+
+    /// This is a compound statement scope.
+    CompoundStmtScope = 0x400000,
   };
 private:
   /// The parent scope for this scope.  This is null for the translation-unit
@@ -429,6 +432,11 @@ public:
   /// \brief Determine whether this scope is a SEH '__except' block.
   bool isSEHExceptScope() const { return getFlags() & Scope::SEHExceptScope; }
 
+  /// \brief Determine whether this scope is a compound statement scope.
+  bool isCompoundStmtScope() const {
+    return getFlags() & Scope::CompoundStmtScope;
+  }
+
   /// \brief Returns if rhs has a higher scope depth than this.
   ///
   /// The caller is responsible for calling this only if one of the two scopes

diff --git a/lib/Parse/ParseCXXInlineMethods.cpp b/lib/Parse/ParseCXXInlineMethods.cpp
index b68559485a5e807f28b8684c2525451353ca776d..c9a895d7d549a0b66f4da28f8c185ea2ea78c1ec 100644 (file)
--- a/lib/Parse/ParseCXXInlineMethods.cpp
+++ b/lib/Parse/ParseCXXInlineMethods.cpp
@@ -518,7 +518,8 @@ void Parser::ParseLexedMethodDef(LexedMethod &LM) {
 
   // Parse the method body. Function body parsing code is similar enough
   // to be re-used for method bodies as well.
-  ParseScope FnScope(this, Scope::FnScope|Scope::DeclScope);
+  ParseScope FnScope(this, Scope::FnScope | Scope::DeclScope |
+                               Scope::CompoundStmtScope);
   Actions.ActOnStartOfFunctionDef(getCurScope(), LM.D);
 
   if (Tok.is(tok::kw_try)) {

diff --git a/lib/Parse/ParseDecl.cpp b/lib/Parse/ParseDecl.cpp
index a4610698c46d03a251b0fd0a6eae578833c45e90..f6a315198c341f28b7308a25fd8ef55d3532ecbf 100644 (file)
--- a/lib/Parse/ParseDecl.cpp
+++ b/lib/Parse/ParseDecl.cpp
@@ -1388,7 +1388,9 @@ void Parser::ParseLexedAttribute(LateParsedAttribute &LA,
 
       // If the Decl is on a function, add function parameters to the scope.
       bool HasFunScope = EnterScope && D->isFunctionOrFunctionTemplate();
-      ParseScope FnScope(this, Scope::FnScope|Scope::DeclScope, HasFunScope);
+      ParseScope FnScope(
+          this, Scope::FnScope | Scope::DeclScope | Scope::CompoundStmtScope,
+          HasFunScope);
       if (HasFunScope)
         Actions.ActOnReenterFunctionContext(Actions.CurScope, D);
 

diff --git a/lib/Parse/ParseExpr.cpp b/lib/Parse/ParseExpr.cpp
index 44b87af01abd0b9d349f50697d6733906a8bbf3f..f4cdc2201af7df895da4d789d159c3cf52ed20ad 100644 (file)
--- a/lib/Parse/ParseExpr.cpp
+++ b/lib/Parse/ParseExpr.cpp
@@ -2881,7 +2881,7 @@ ExprResult Parser::ParseBlockLiteralExpression() {
   // allows determining whether a variable reference inside the block is
   // within or outside of the block.
   ParseScope BlockScope(this, Scope::BlockScope | Scope::FnScope |
-                              Scope::DeclScope);
+                                  Scope::CompoundStmtScope | Scope::DeclScope);
 
   // Inform sema that we are starting a block.
   Actions.ActOnBlockStart(CaretLoc, getCurScope());

diff --git a/lib/Parse/ParseExprCXX.cpp b/lib/Parse/ParseExprCXX.cpp
index dcafbadae5c0865e08d7bcd1e365ee59f93ecb6d..56b0327995763cf7236b5cd3c16ea06b955fe74d 100644 (file)
--- a/lib/Parse/ParseExprCXX.cpp
+++ b/lib/Parse/ParseExprCXX.cpp
@@ -1281,7 +1281,8 @@ ExprResult Parser::ParseLambdaExpressionAfterIntroducer(
 
   // FIXME: Rename BlockScope -> ClosureScope if we decide to continue using
   // it.
-  unsigned ScopeFlags = Scope::BlockScope | Scope::FnScope | Scope::DeclScope;
+  unsigned ScopeFlags = Scope::BlockScope | Scope::FnScope | Scope::DeclScope |
+                        Scope::CompoundStmtScope;
   ParseScope BodyScope(this, ScopeFlags);
 
   Actions.ActOnStartOfLambdaDefinition(Intro, D, getCurScope());

diff --git a/lib/Parse/ParseObjc.cpp b/lib/Parse/ParseObjc.cpp
index 01b1bf48e473891cc892a51e1657d1a90b699276..edf1da171b08d874fd5d79bf9cbe7b596c414e76 100644 (file)
--- a/lib/Parse/ParseObjc.cpp
+++ b/lib/Parse/ParseObjc.cpp
@@ -2478,7 +2478,7 @@ Parser::ParseObjCSynchronizedStmt(SourceLocation atLoc) {
     operand = Actions.ActOnObjCAtSynchronizedOperand(atLoc, operand.get());
 
   // Parse the compound statement within a new scope.
-  ParseScope bodyScope(this, Scope::DeclScope);
+  ParseScope bodyScope(this, Scope::DeclScope | Scope::CompoundStmtScope);
   StmtResult body(ParseCompoundStatementBody());
   bodyScope.Exit();
 
@@ -2514,7 +2514,7 @@ StmtResult Parser::ParseObjCTryStmt(SourceLocation atLoc) {
   }
   StmtVector CatchStmts;
   StmtResult FinallyStmt;
-  ParseScope TryScope(this, Scope::DeclScope);
+  ParseScope TryScope(this, Scope::DeclScope | Scope::CompoundStmtScope);
   StmtResult TryBody(ParseCompoundStatementBody());
   TryScope.Exit();
   if (TryBody.isInvalid())
@@ -2535,7 +2535,9 @@ StmtResult Parser::ParseObjCTryStmt(SourceLocation atLoc) {
       ConsumeToken(); // consume catch
       if (Tok.is(tok::l_paren)) {
         ConsumeParen();
-        ParseScope CatchScope(this, Scope::DeclScope|Scope::AtCatchScope);
+        ParseScope CatchScope(this, Scope::DeclScope |
+                                        Scope::CompoundStmtScope |
+                                        Scope::AtCatchScope);
         if (Tok.isNot(tok::ellipsis)) {
           DeclSpec DS(AttrFactory);
           ParseDeclarationSpecifiers(DS);
@@ -2579,7 +2581,8 @@ StmtResult Parser::ParseObjCTryStmt(SourceLocation atLoc) {
     } else {
       assert(Tok.isObjCAtKeyword(tok::objc_finally) && "Lookahead confused?");
       ConsumeToken(); // consume finally
-      ParseScope FinallyScope(this, Scope::DeclScope);
+      ParseScope FinallyScope(this,
+                              Scope::DeclScope | Scope::CompoundStmtScope);
 
       StmtResult FinallyBody(true);
       if (Tok.is(tok::l_brace))
@@ -2616,7 +2619,7 @@ Parser::ParseObjCAutoreleasePoolStmt(SourceLocation atLoc) {
   }
   // Enter a scope to hold everything within the compound stmt.  Compound
   // statements can always hold declarations.
-  ParseScope BodyScope(this, Scope::DeclScope);
+  ParseScope BodyScope(this, Scope::DeclScope | Scope::CompoundStmtScope);
 
   StmtResult AutoreleasePoolBody(ParseCompoundStatementBody());
 
@@ -3650,11 +3653,10 @@ void Parser::ParseLexedObjCMethodDefs(LexedMethod &LM, bool parseMethod) {
   assert(Tok.isOneOf(tok::l_brace, tok::kw_try, tok::colon) && 
          "Inline objective-c method not starting with '{' or 'try' or ':'");
   // Enter a scope for the method or c-function body.
-  ParseScope BodyScope(this,
-                       parseMethod
-                       ? Scope::ObjCMethodScope|Scope::FnScope|Scope::DeclScope
-                       : Scope::FnScope|Scope::DeclScope);
-    
+  ParseScope BodyScope(this, (parseMethod ? Scope::ObjCMethodScope : 0) |
+                                 Scope::FnScope | Scope::DeclScope |
+                                 Scope::CompoundStmtScope);
+
   // Tell the actions module that we have entered a method or c-function definition 
   // with the specified Declarator for the method/function.
   if (parseMethod)

diff --git a/lib/Parse/ParseOpenMP.cpp b/lib/Parse/ParseOpenMP.cpp
index 353b0795f661523619b32968c6b8949acbaf310f..f5638773d9046e5d625482e49d2d773debc81c00 100644 (file)
--- a/lib/Parse/ParseOpenMP.cpp
+++ b/lib/Parse/ParseOpenMP.cpp
@@ -302,6 +302,7 @@ Parser::ParseOpenMPDeclareReductionDirective(AccessSpecifier AS) {
   for (auto *D : DRD.get()) {
     TentativeParsingAction TPA(*this);
     ParseScope OMPDRScope(this, Scope::FnScope | Scope::DeclScope |
+                                    Scope::CompoundStmtScope |
                                     Scope::OpenMPDirectiveScope);
     // Parse <combiner> expression.
     Actions.ActOnOpenMPDeclareReductionCombinerStart(getCurScope(), D);
@@ -337,6 +338,7 @@ Parser::ParseOpenMPDeclareReductionDirective(AccessSpecifier AS) {
           IsCorrect;
       if (Tok.isNot(tok::annot_pragma_openmp_end)) {
         ParseScope OMPDRScope(this, Scope::FnScope | Scope::DeclScope |
+                                        Scope::CompoundStmtScope |
                                         Scope::OpenMPDirectiveScope);
         // Parse expression.
         Actions.ActOnOpenMPDeclareReductionInitializerStart(getCurScope(), D);
@@ -405,8 +407,9 @@ public:
 
     // If the Decl is on a function, add function parameters to the scope.
     HasFunScope = D->isFunctionOrFunctionTemplate();
-    FnScope = new Parser::ParseScope(&P, Scope::FnScope | Scope::DeclScope,
-                                     HasFunScope);
+    FnScope = new Parser::ParseScope(
+        &P, Scope::FnScope | Scope::DeclScope | Scope::CompoundStmtScope,
+        HasFunScope);
     if (HasFunScope)
       Actions.ActOnReenterFunctionContext(Actions.getCurScope(), D);
   }
@@ -813,8 +816,8 @@ StmtResult Parser::ParseOpenMPDeclarativeOrExecutableDirective(
   SmallVector<OMPClause *, 5> Clauses;
   SmallVector<llvm::PointerIntPair<OMPClause *, 1, bool>, OMPC_unknown + 1>
   FirstClauses(OMPC_unknown + 1);
-  unsigned ScopeFlags =
-      Scope::FnScope | Scope::DeclScope | Scope::OpenMPDirectiveScope;
+  unsigned ScopeFlags = Scope::FnScope | Scope::DeclScope |
+                        Scope::CompoundStmtScope | Scope::OpenMPDirectiveScope;
   SourceLocation Loc = ConsumeAnnotationToken(), EndLoc;
   auto DKind = ParseOpenMPDirectiveKind(*this);
   OpenMPDirectiveKind CancelRegion = OMPD_unknown;

diff --git a/lib/Parse/ParsePragma.cpp b/lib/Parse/ParsePragma.cpp
index c5215ffceebc920dc125b54c7ba7144521b0f663..198d5c6e9cb0387a2ed07a0cf4ddfcf6a5269d20 100644 (file)
--- a/lib/Parse/ParsePragma.cpp
+++ b/lib/Parse/ParsePragma.cpp
@@ -533,7 +533,8 @@ StmtResult Parser::HandlePragmaCaptured()
 
   SourceLocation Loc = Tok.getLocation();
 
-  ParseScope CapturedRegionScope(this, Scope::FnScope | Scope::DeclScope);
+  ParseScope CapturedRegionScope(this, Scope::FnScope | Scope::DeclScope |
+                                           Scope::CompoundStmtScope);
   Actions.ActOnCapturedRegionStart(Loc, getCurScope(), CR_Default,
                                    /*NumParams=*/1);
 

diff --git a/lib/Parse/ParseStmt.cpp b/lib/Parse/ParseStmt.cpp
index b1fbb20c721bdf6edc8936fec3070b1ee4c18ef1..65c3f21f2d9199bead203f3f0e4aa3550b15bedc 100644 (file)
--- a/lib/Parse/ParseStmt.cpp
+++ b/lib/Parse/ParseStmt.cpp
@@ -453,9 +453,10 @@ StmtResult Parser::ParseSEHTryBlock() {
   if (Tok.isNot(tok::l_brace))
     return StmtError(Diag(Tok, diag::err_expected) << tok::l_brace);
 
-  StmtResult TryBlock(ParseCompoundStatement(/*isStmtExpr=*/false,
-                      Scope::DeclScope | Scope::SEHTryScope));
-  if(TryBlock.isInvalid())
+  StmtResult TryBlock(ParseCompoundStatement(
+      /*isStmtExpr=*/false,
+      Scope::DeclScope | Scope::CompoundStmtScope | Scope::SEHTryScope));
+  if (TryBlock.isInvalid())
     return TryBlock;
 
   StmtResult Handler;
@@ -840,7 +841,8 @@ StmtResult Parser::ParseDefaultStatement() {
 }
 
 StmtResult Parser::ParseCompoundStatement(bool isStmtExpr) {
-  return ParseCompoundStatement(isStmtExpr, Scope::DeclScope);
+  return ParseCompoundStatement(isStmtExpr,
+                                Scope::DeclScope | Scope::CompoundStmtScope);
 }
 
 /// ParseCompoundStatement - Parse a "{}" block.
@@ -2085,9 +2087,10 @@ StmtResult Parser::ParseCXXTryBlockCommon(SourceLocation TryLoc, bool FnTry) {
   if (Tok.isNot(tok::l_brace))
     return StmtError(Diag(Tok, diag::err_expected) << tok::l_brace);
 
-  StmtResult TryBlock(ParseCompoundStatement(/*isStmtExpr=*/false,
-                      Scope::DeclScope | Scope::TryScope |
-                        (FnTry ? Scope::FnTryCatchScope : 0)));
+  StmtResult TryBlock(ParseCompoundStatement(
+      /*isStmtExpr=*/false, Scope::DeclScope | Scope::TryScope |
+                                Scope::CompoundStmtScope |
+                                (FnTry ? Scope::FnTryCatchScope : 0)));
   if (TryBlock.isInvalid())
     return TryBlock;
 

diff --git a/lib/Parse/ParseTemplate.cpp b/lib/Parse/ParseTemplate.cpp
index 944cd775d52a4eef8eff1b153584c24e8e5762a9..fc1722ea6cd0ea0956c0fce6c4fdbe2d8389dde6 100644 (file)
--- a/lib/Parse/ParseTemplate.cpp
+++ b/lib/Parse/ParseTemplate.cpp
@@ -1380,7 +1380,8 @@ void Parser::ParseLateTemplatedFuncDef(LateParsedTemplate &LPT) {
 
   // Parse the method body. Function body parsing code is similar enough
   // to be re-used for method bodies as well.
-  ParseScope FnScope(this, Scope::FnScope|Scope::DeclScope);
+  ParseScope FnScope(this, Scope::FnScope | Scope::DeclScope |
+                               Scope::CompoundStmtScope);
 
   // Recreate the containing function DeclContext.
   Sema::ContextRAII FunctionSavedContext(Actions,

diff --git a/lib/Parse/Parser.cpp b/lib/Parse/Parser.cpp
index 4aa9a5971929193d88b012d7dac0c504e704703a..51f4957a6e80cdf3274d70042c07b371dfb0b5b1 100644 (file)
--- a/lib/Parse/Parser.cpp
+++ b/lib/Parse/Parser.cpp
@@ -1075,8 +1075,9 @@ Decl *Parser::ParseFunctionDefinition(ParsingDeclarator &D,
       TemplateInfo.Kind == ParsedTemplateInfo::Template &&
       Actions.canDelayFunctionBody(D)) {
     MultiTemplateParamsArg TemplateParameterLists(*TemplateInfo.TemplateParams);
-    
-    ParseScope BodyScope(this, Scope::FnScope|Scope::DeclScope);
+
+    ParseScope BodyScope(this, Scope::FnScope | Scope::DeclScope |
+                                   Scope::CompoundStmtScope);
     Scope *ParentScope = getCurScope()->getParent();
 
     D.setFunctionDefinitionKind(FDK_Definition);
@@ -1106,7 +1107,8 @@ Decl *Parser::ParseFunctionDefinition(ParsingDeclarator &D,
            (Tok.is(tok::l_brace) || Tok.is(tok::kw_try) ||
             Tok.is(tok::colon)) && 
       Actions.CurContext->isTranslationUnit()) {
-    ParseScope BodyScope(this, Scope::FnScope|Scope::DeclScope);
+    ParseScope BodyScope(this, Scope::FnScope | Scope::DeclScope |
+                                   Scope::CompoundStmtScope);
     Scope *ParentScope = getCurScope()->getParent();
 
     D.setFunctionDefinitionKind(FDK_Definition);
@@ -1124,7 +1126,8 @@ Decl *Parser::ParseFunctionDefinition(ParsingDeclarator &D,
   }
 
   // Enter a scope for the function body.
-  ParseScope BodyScope(this, Scope::FnScope|Scope::DeclScope);
+  ParseScope BodyScope(this, Scope::FnScope | Scope::DeclScope |
+                                 Scope::CompoundStmtScope);
 
   // Tell the actions module that we have entered a function definition with the
   // specified Declarator for the function.

diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index 6bcb0231743fd280d15d277fbfebe601346b1268..d19ace9c43bc2094dff2820316dbc7fbbd4fd9ee 100644 (file)
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -12677,12 +12677,16 @@ NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc,
                 SourceLocation());
   D.SetIdentifier(&II, Loc);
 
-  // Insert this function into translation-unit scope.
+  // Insert this function into the enclosing block scope.
+  while (S && !S->isCompoundStmtScope())
+    S = S->getParent();
+  if (S == nullptr)
+    S = TUScope;
 
   DeclContext *PrevDC = CurContext;
   CurContext = Context.getTranslationUnitDecl();
 
-  FunctionDecl *FD = cast<FunctionDecl>(ActOnDeclarator(TUScope, D));
+  FunctionDecl *FD = cast<FunctionDecl>(ActOnDeclarator(S, D));
   FD->setImplicit();
 
   CurContext = PrevDC;

diff --git a/test/Sema/implicit-decl-c90.c b/test/Sema/implicit-decl-c90.c
new file mode 100644 (file)
index 0000000..38b0175
--- /dev/null
+++ b/test/Sema/implicit-decl-c90.c
@@ -0,0 +1,39 @@
+// RUN: %clang_cc1 %s -std=c90 -verify -fsyntax-only
+void t0(int x) {
+  int (*p)();
+  if(x > 0)
+    x = g() + 1;
+  p = g;
+  if(x < 0) {
+    extern void u(int (*)[h()]);
+    int (*q)() = h;
+  }
+  p = h; /* expected-error {{use of undeclared identifier 'h'}} */
+}
+
+void t1(int x) {
+  int (*p)();
+  switch (x) {
+    g();
+  case 0:
+    x = h() + 1;
+    break;
+  case 1:
+    p = g;
+    p = h;
+    break;
+  }
+  p = g; /* expected-error {{use of undeclared identifier 'g'}} */
+  p = h; /* expected-error {{use of undeclared identifier 'h'}} */
+}
+
+int t2(int x) {
+  int y = ({ if (x > 0) x = g() + 1; 2*x; });
+  int (*p)() = g; /* expected-error {{use of undeclared identifier 'g'}} */
+  return y;
+}
+
+int (*p)() = g; /* expected-error {{use of undeclared identifier 'g'}} */
+int (*q)() = h; /* expected-error {{use of undeclared identifier 'h'}} */
+
+float g(); /* not expecting conflicting types diagnostics here */

diff --git a/test/Sema/implicit-decl.c b/test/Sema/implicit-decl.c
index ffab9a6f913c41e298e9316556122a226396e0bf..0a8920107836bb6fb4efdb2226f0fee23dfaf5d8 100644 (file)
--- a/test/Sema/implicit-decl.c
+++ b/test/Sema/implicit-decl.c
@@ -9,8 +9,7 @@ void func() {
    int32_t *vector[16];
    const char compDesc[16 + 1];
    int32_t compCount = 0;
-   if (_CFCalendarDecomposeAbsoluteTimeV(compDesc, vector, compCount)) { // expected-note {{previous implicit declaration is here}} \
-         expected-error {{implicit declaration of function '_CFCalendarDecomposeAbsoluteTimeV' is invalid in C99}}
+   if (_CFCalendarDecomposeAbsoluteTimeV(compDesc, vector, compCount)) { // expected-error {{implicit declaration of function '_CFCalendarDecomposeAbsoluteTimeV' is invalid in C99}}
    }
 
    printg("Hello, World!\n"); // expected-error{{implicit declaration of function 'printg' is invalid in C99}} \
@@ -18,7 +17,7 @@ void func() {
 
   __builtin_is_les(1, 3); // expected-error{{use of unknown builtin '__builtin_is_les'}}
 }
-Boolean _CFCalendarDecomposeAbsoluteTimeV(const char *componentDesc, int32_t **vector, int32_t count) { // expected-error{{conflicting types for '_CFCalendarDecomposeAbsoluteTimeV'}}
+Boolean _CFCalendarDecomposeAbsoluteTimeV(const char *componentDesc, int32_t **vector, int32_t count) {
  return 0;
 }