Clean up the C89/C++ warnings about C99 array features to not

emit duplicate diags (some in parser and some in sema) and to
warn about use of typequals in array sizes.  This implements
PR2759.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@61197 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/clang/Basic/DiagnosticKinds.def b/include/clang/Basic/DiagnosticKinds.def
index 38d084fc99cc7d204c4dee2c9bc62739c5c7df9f..39464efd6aec760ae8a16da6c57cdb5a2fbcf83f 100644 (file)
--- a/include/clang/Basic/DiagnosticKinds.def
+++ b/include/clang/Basic/DiagnosticKinds.def
@@ -310,7 +310,7 @@ DIAG(warn_enum_value_overflow, WARNING,
 DIAG(ext_ident_list_in_param, EXTENSION,
      "type-less parameter names in function declaration")
 DIAG(ext_c99_array_usage, EXTENSION,
-     "use of C99-specific array features")
+     "use of C99-specific array features, accepted as an extension")
 DIAG(ext_c99_variable_decl_in_for_loop, EXTENSION,
      "variable declaration in for loop is a C99-specific feature")
 DIAG(ext_c99_compound_literal, EXTENSION,

diff --git a/lib/Parse/ParseDecl.cpp b/lib/Parse/ParseDecl.cpp
index 1a8e5d9f95567e76401a3bfc747965fccd25222f..e31b87bd4322bd3854d81d90cd0607ffe2eec29c 100644 (file)
--- a/lib/Parse/ParseDecl.cpp
+++ b/lib/Parse/ParseDecl.cpp
@@ -1283,7 +1283,7 @@ void Parser::ParseTypeQualifierListOpt(DeclSpec &DS) {
       DS.AddAttributes(ParseAttributes());
       continue; // do *not* consume the next token!
     }
-    
+
     // If the specifier combination wasn't legal, issue a diagnostic.
     if (isInvalid) {
       assert(PrevSpec && "Method did not return previous specifier!");
@@ -1943,6 +1943,7 @@ void Parser::ParseBracketDeclarator(Declarator &D) {
     StaticLoc = ConsumeToken();
   
   // If there is a type-qualifier-list, read it now.
+  // Type qualifiers in an array subscript are a C99 feature.
   DeclSpec DS;
   ParseTypeQualifierListOpt(DS);
   
@@ -1962,9 +1963,10 @@ void Parser::ParseBracketDeclarator(Declarator &D) {
   if (Tok.is(tok::star) && GetLookAheadToken(1).is(tok::r_square)) {
     ConsumeToken();  // Eat the '*'.
 
-    if (StaticLoc.isValid())
+    if (StaticLoc.isValid()) {
       Diag(StaticLoc, diag::err_unspecified_vla_size_with_static);
-    StaticLoc = SourceLocation();  // Drop the static.
+      StaticLoc = SourceLocation();  // Drop the static.
+    }
     isStar = true;
   } else if (Tok.isNot(tok::r_square)) {
     // Parse the assignment-expression now.
@@ -1980,15 +1982,6 @@ void Parser::ParseBracketDeclarator(Declarator &D) {
   
   MatchRHSPunctuation(tok::r_square, StartLoc);
     
-  // If C99 isn't enabled, emit an ext-warn if the arg list wasn't empty and if
-  // it was not a constant expression.
-  if (!getLang().C99) {
-    // TODO: check C90 array constant exprness.
-    if (isStar || StaticLoc.isValid() ||
-        0/*TODO: NumElts is not a C90 constantexpr */)
-      Diag(StartLoc, diag::ext_c99_array_usage);
-  }
-
   // Remember that we parsed a pointer type, and remember the type-quals.
   D.AddTypeInfo(DeclaratorChunk::getArray(DS.getTypeQualifiers(),
                                           StaticLoc.isValid(), isStar,

diff --git a/lib/Sema/SemaType.cpp b/lib/Sema/SemaType.cpp
index 3f911f5b0cde10888f7657cfe667b1221ba33542..a6441c8d7040c8385848e11f54950828efa1fb79 100644 (file)
--- a/lib/Sema/SemaType.cpp
+++ b/lib/Sema/SemaType.cpp
@@ -416,11 +416,13 @@ QualType Sema::GetTypeForDeclarator(Declarator &D, Scope *S, unsigned Skip) {
         T = Context.getConstantArrayType(T, ConstVal, ASM, ATI.TypeQuals);
       }
       // If this is not C99, extwarn about VLA's and C99 array size modifiers.
-      if (!getLangOptions().C99 &&
-          (ASM != ArrayType::Normal ||
-           (ArraySize && !ArraySize->isValueDependent() && 
-            !ArraySize->isIntegerConstantExpr(Context))))
-        Diag(D.getIdentifierLoc(), diag::ext_vla);
+      if (!getLangOptions().C99) {
+        if (ArraySize && !ArraySize->isValueDependent() && 
+            !ArraySize->isIntegerConstantExpr(Context))
+          Diag(D.getIdentifierLoc(), diag::ext_vla);
+        else if (ASM != ArrayType::Normal || ATI.TypeQuals != 0)
+          Diag(D.getIdentifierLoc(), diag::ext_c99_array_usage);
+      }
       break;
     }
     case DeclaratorChunk::Function:

diff --git a/test/Sema/c89.c b/test/Sema/c89.c
index b1780e916102440950e82088b7b09029eddbcaa8..0c7496ac7a27fefd53786e6bb9e0d2568c116dc8 100644 (file)
--- a/test/Sema/c89.c
+++ b/test/Sema/c89.c
@@ -60,3 +60,10 @@ void foo(T); /* typedef for void is allowed */
 
 void foo(void) {}
 
+/* PR2759 */
+void test10 (int x[*]); /* expected-warning {{use of C99-specific array features}} */
+void test11 (int x[static 4]); /* expected-warning {{use of C99-specific array features}} */
+
+void test12 (int x[const 4]) { /* expected-warning {{use of C99-specific array features}} */
+  int Y[x[1]]; /* expected-warning {{variable length arrays are a C99 feature, accepted as an extension}} */
+}