Enum fixes

src/aro/Type.zig

@@ -1220,6 +1220,10 @@ pub fn eql(a_param: Type, b_param: Type, comp: *const Compilation, check_qualifi
         if (!b.isFunc()) return false;
     } else if (a.isArray()) {
         if (!b.isArray()) return false;
+    } else if (a.specifier == .@"enum" and a.data.@"enum".fixed and b.specifier != .@"enum") {
+        return a.data.@"enum".tag_ty.eql(b, comp, check_qualifiers);
+    } else if (b.specifier == .@"enum" and b.data.@"enum".fixed and a.specifier != .@"enum") {
+        return a.eql(b.data.@"enum".tag_ty, comp, check_qualifiers);
     } else if (a.specifier != b.specifier) return false;
 
     if (a.qual.atomic != b.qual.atomic) return false;
@@ -1314,13 +1318,18 @@ pub fn integerRank(ty: Type, comp: *const Compilation) usize {
         .typeof_expr => ty.data.expr.ty.integerRank(comp),
         .attributed => ty.data.attributed.base.integerRank(comp),
 
+        .@"enum" => {
+            std.debug.assert(real.data.@"enum".fixed);
+            return real.data.@"enum".tag_ty.integerRank(comp);
+        },
         else => unreachable,
     });
 }
 
 /// Returns true if `a` and `b` are integer types that differ only in sign
 pub fn sameRankDifferentSign(a: Type, b: Type, comp: *const Compilation) bool {
     if (!a.isInt() or !b.isInt()) return false;
+    if (a.hasIncompleteSize() or b.hasIncompleteSize()) return false;
     if (a.integerRank(comp) != b.integerRank(comp)) return false;
     return a.isUnsignedInt(comp) != b.isUnsignedInt(comp);
 }

test/cases/enum fixed.c

@@ -34,6 +34,43 @@ enum E e;
 enum E: int;
 void fn(enum E);
 
+enum Signed: int {
+    S,
+};
+
+enum Signed2: int {
+    S2,
+};
+
+enum Unsigned: unsigned {
+    U,
+};
+
+enum Plain {
+    P,
+};
+
+_Static_assert(!__builtin_types_compatible_p(enum Signed, enum Signed2), "");
+_Static_assert(!__builtin_types_compatible_p(enum Signed, enum Unsigned), "");
+_Static_assert(__builtin_types_compatible_p(enum Signed, int), "");
+_Static_assert(__builtin_types_compatible_p(enum Unsigned, unsigned), "");
+
+_Static_assert(!__builtin_types_compatible_p(enum Signed, enum Plain), "");
+_Static_assert(!__builtin_types_compatible_p(enum Unsigned, enum Plain), "");
+
+void pointers(void) {
+    int x;
+    unsigned y;
+
+    enum Signed *e1 = &x;
+    enum Signed *e2 = &y;
+    enum Unsigned *e3 = &x;
+    enum Unsigned *e4 = &y;
+
+    enum Incomplete *i1 = &x;
+    enum Incomplete *i2 = &y;
+}
+
 #define EXPECTED_ERRORS "enum fixed.c:2:7: warning: enumeration types with a fixed underlying type are a Clang extension [-Wfixed-enum-extension]" \
     "enum fixed.c:4:6: error: enumeration previously declared with fixed underlying type" \
     "enum fixed.c:2:6: note: previous definition is here" \
@@ -43,3 +80,8 @@ void fn(enum E);
     "enum fixed.c:9:6: note: previous definition is here" \
     "enum fixed.c:14:5: error: enumerator value is not representable in the underlying type 'unsigned char'" \
     "enum fixed.c:18:5: error: enumerator value is not representable in the underlying type 'char'" \
+    "enum fixed.c:66:23: warning: incompatible pointer types initializing 'enum Signed: int *' from incompatible type 'unsigned int *' converts between pointers to integer types with different sign [-Wpointer-sign]" \
+    "enum fixed.c:67:25: warning: incompatible pointer types initializing 'enum Unsigned: unsigned int *' from incompatible type 'int *' [-Wincompatible-pointer-types]" \
+    "enum fixed.c:70:27: warning: incompatible pointer types initializing 'enum Incomplete *' from incompatible type 'int *' [-Wincompatible-pointer-types]" \
+    "enum fixed.c:71:27: warning: incompatible pointer types initializing 'enum Incomplete *' from incompatible type 'unsigned int *' [-Wincompatible-pointer-types]" \
+