diff --git a/src/Module.zig b/src/Module.zig
index 9a5a23b5772b..f3c5cc0c4e82 100644
--- a/src/Module.zig
+++ b/src/Module.zig
@@ -2771,6 +2771,11 @@ pub fn resolvePeerTypes(self: *Module, scope: *Scope, instructions: []*Inst) !Ty
             chosen = candidate;
             continue;
         }
+
+        // error set widening
+        // TODO remove: dest is chosen, cur is canditade
+        if (chosen.ty.zigTypeTag() == .ErrorSet and candidate.ty.zigTypeTag() == .ErrorSet) {}
+
         if (chosen.ty.isInt() and
             candidate.ty.isInt() and
             chosen.ty.isSignedInt() == candidate.ty.isSignedInt())
diff --git a/src/type.zig b/src/type.zig
index a6aa0dfd445b..50100f6c16cf 100644
--- a/src/type.zig
+++ b/src/type.zig
@@ -240,6 +240,8 @@ pub const Type = extern union {
                         return true
                     else
                         return false;
+                } else if (b.tag() == .anyerror) {
+                    return false;
                 }
 
                 if (a.tag() == .error_set_single and b.tag() == .error_set_single) {
diff --git a/src/zir_sema.zig b/src/zir_sema.zig
index 2bbeef3a2f81..5b04ae3cddf4 100644
--- a/src/zir_sema.zig
+++ b/src/zir_sema.zig
@@ -886,8 +886,8 @@ fn analyzeInstMergeErrorSets(mod: *Module, scope: *Scope, inst: *zir.Inst.BinOp)
 
     switch (lhs_fields) {
         .err_single => |name| {
-            const entry = mod.global_error_set.get(name).?;
-            payload.fields.putAssumeCapacity(name, entry);
+            const num = mod.global_error_set.get(name).?;
+            payload.fields.putAssumeCapacity(name, num);
         },
         .multiple => |multiple| {
             var it = multiple.iterator();
@@ -900,8 +900,8 @@ fn analyzeInstMergeErrorSets(mod: *Module, scope: *Scope, inst: *zir.Inst.BinOp)
 
     switch (rhs_fields) {
         .err_single => |name| {
-            const entry = try mod.getErrorValue(name);
-            payload.fields.putAssumeCapacity(entry.key, entry.value);
+            const num = mod.global_error_set.get(name).?;
+            payload.fields.putAssumeCapacity(name, num);
         },
         .multiple => |multiple| {
             var it = multiple.iterator();
@@ -1823,13 +1823,10 @@ fn analyzeInstCmp(
         if (!is_equality_cmp) {
             return mod.fail(scope, inst.base.src, "{} operator not allowed for errors", .{@tagName(op)});
         }
-        const lhs_comptime = lhs.ty.cast(Type.Payload.ErrorSetSingle);
-        const rhs_comptime = rhs.ty.cast(Type.Payload.ErrorSetSingle);
-        if (lhs_comptime != null and rhs_comptime != null) {
-            if (op == .eq)
-                return mod.constBool(scope, inst.base.src, !std.mem.eql(u8, lhs_comptime.?.name, rhs_comptime.?.name))
-            else
-                return mod.constBool(scope, inst.base.src, std.mem.eql(u8, lhs_comptime.?.name, rhs_comptime.?.name));
+        const lhs_val = lhs.value();
+        const rhs_val = rhs.value();
+        if (lhs_val != null and rhs_val != null) {
+            return mod.constBool(scope, inst.base.src, !(lhs_val.?.cast(Value.Payload.Error).?.value == rhs_val.?.cast(Value.Payload.Error).?.value) == (op == .eq));
         }
         return mod.fail(scope, inst.base.src, "TODO runtime error comparison", .{});
     } else if (lhs.ty.isNumeric() and rhs.ty.isNumeric()) {