[PATCH] D75758: [Sema] Add -Wpointer-to-enum-cast and -Wvoid-pointer-to-enum-cast

[Nathan Chancellor via Phabricator via cfe-commits]

nathanchance updated this revision to Diff 248824.
nathanchance edited the summary of this revision.

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D75758/new/

https://reviews.llvm.org/D75758

Files:
  clang/include/clang/Basic/DiagnosticGroups.td
  clang/include/clang/Basic/DiagnosticSemaKinds.td
  clang/lib/Sema/SemaCast.cpp
  clang/test/Sema/cast.c


Index: clang/test/Sema/cast.c
===================================================================
--- clang/test/Sema/cast.c
+++ clang/test/Sema/cast.c
@@ -186,3 +186,23 @@
 void *intToPointerCast3() {
   return (void*)(1 + 3);
 }
+
+void voidPointerToEnumCast(VoidPtr v) {
+  (void)(X) v; // expected-warning{{cast to smaller integer type 'X' from 'VoidPtr' (aka 'void *')}}
+  // Test that casts to void* can be controlled separately
+  // from other -Wpointer-to-enum-cast warnings.
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wvoid-pointer-to-enum-cast"
+  (void)(X) v; // no-warning
+#pragma clang diagnostic pop
+}
+
+void pointerToEnumCast(CharPtr v) {
+  (void)(X) v; // expected-warning{{cast to smaller integer type 'X' from 'CharPtr' (aka 'char *')}}
+  // Test that casts to void* can be controlled separately
+  // from other -Wpointer-to-enum-cast warnings.
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wvoid-pointer-to-enum-cast"
+  (void)(X) v; // expected-warning{{cast to smaller integer type 'X' from 'CharPtr' (aka 'char *')}}
+#pragma clang diagnostic pop
+}
Index: clang/lib/Sema/SemaCast.cpp
===================================================================
--- clang/lib/Sema/SemaCast.cpp
+++ clang/lib/Sema/SemaCast.cpp
@@ -2777,11 +2777,18 @@
       // If the result cannot be represented in the integer type, the behavior
       // is undefined. The result need not be in the range of values of any
       // integer type.
-      unsigned Diag = Self.getLangOpts().MicrosoftExt
-                          ? diag::ext_ms_pointer_to_int_cast
-                          : SrcType->isVoidPointerType()
-                                ? diag::warn_void_pointer_to_int_cast
-                                : diag::warn_pointer_to_int_cast;
+      unsigned Diag;
+      if (Self.getLangOpts().MicrosoftExt)
+        Diag = diag::ext_ms_pointer_to_int_cast;
+      else if (SrcType->isVoidPointerType())
+        if (DestType->isEnumeralType())
+          Diag = diag::warn_void_pointer_to_enum_cast;
+        else
+          Diag = diag::warn_void_pointer_to_int_cast;
+      else if (DestType->isEnumeralType())
+        Diag = diag::warn_pointer_to_enum_cast;
+      else
+        Diag = diag::warn_pointer_to_int_cast;
       Self.Diag(OpRange.getBegin(), Diag) << SrcType << DestType << OpRange;
     }
   }
Index: clang/include/clang/Basic/DiagnosticSemaKinds.td
===================================================================
--- clang/include/clang/Basic/DiagnosticSemaKinds.td
+++ clang/include/clang/Basic/DiagnosticSemaKinds.td
@@ -3669,9 +3669,15 @@
 def warn_pointer_to_int_cast : Warning<
   "cast to smaller integer type %1 from %0">,
   InGroup<PointerToIntCast>;
+def warn_pointer_to_enum_cast : Warning<
+  warn_pointer_to_int_cast.Text>,
+  InGroup<PointerToEnumCast>;
 def warn_void_pointer_to_int_cast : Warning<
   "cast to smaller integer type %1 from %0">,
   InGroup<VoidPointerToIntCast>;
+def warn_void_pointer_to_enum_cast : Warning<
+  warn_void_pointer_to_int_cast.Text>,
+  InGroup<VoidPointerToEnumCast>;
 def ext_ms_pointer_to_int_cast : ExtWarn<
   "cast to smaller integer type %1 from %0 is a Microsoft extension">,
 InGroup<MicrosoftCast>;
Index: clang/include/clang/Basic/DiagnosticGroups.td
===================================================================
--- clang/include/clang/Basic/DiagnosticGroups.td
+++ clang/include/clang/Basic/DiagnosticGroups.td
@@ -838,9 +838,13 @@
 def IntToVoidPointerCast : DiagGroup<"int-to-void-pointer-cast">;
 def IntToPointerCast : DiagGroup<"int-to-pointer-cast",
                                  [IntToVoidPointerCast]>;
-def VoidPointerToIntCast : DiagGroup<"void-pointer-to-int-cast">;
+def VoidPointerToEnumCast : DiagGroup<"void-pointer-to-enum-cast">;
+def VoidPointerToIntCast : DiagGroup<"void-pointer-to-int-cast",
+                                     [VoidPointerToEnumCast]>;
+def PointerToEnumCast : DiagGroup<"pointer-to-enum-cast",
+                                  [VoidPointerToEnumCast]>;
 def PointerToIntCast : DiagGroup<"pointer-to-int-cast",
-                                 [VoidPointerToIntCast]>;
+                                 [PointerToEnumCast, VoidPointerToIntCast]>;
 
 def Move : DiagGroup<"move", [
     PessimizingMove,


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D75758.248824.patch
Type: text/x-patch
Size: 4310 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/cfe-commits/attachments/20200306/af48b518/attachment-0001.bin>