Push a generic region when handling a `where` expression. (#4340)

This fixes a crash in the case where a `where` expression appears
outside of any generic.

toolchain/check/generic.cpp

@@ -295,6 +295,10 @@ auto RebuildGenericEvalBlock(Context& context, SemIR::GenericId generic_id,
   return context.inst_block_stack().Pop();
 }
 
+auto DiscardGenericDecl(Context& context) -> void {
+  context.generic_region_stack().Pop();
+}
+
 auto FinishGenericDecl(Context& context, SemIR::InstId decl_id)
     -> SemIR::GenericId {
   auto all_bindings =

toolchain/check/generic.h

@@ -16,6 +16,11 @@ auto StartGenericDecl(Context& context) -> void;
 // Start processing a declaration or definition that might be a generic entity.
 auto StartGenericDefinition(Context& context) -> void;
 
+// Discard the information about the current generic entity. This should be
+// called instead of `FinishGenericDecl` if the corresponding `Generic` object
+// would not actually be used, or when recovering from an error.
+auto DiscardGenericDecl(Context& context) -> void;
+
 // Finish processing a potentially generic declaration and produce a
 // corresponding generic object. Returns SemIR::GenericId::Invalid if this
 // declaration is not actually generic.

toolchain/check/handle_where.cpp

@@ -4,6 +4,7 @@
 
 #include "toolchain/check/context.h"
 #include "toolchain/check/convert.h"
+#include "toolchain/check/generic.h"
 #include "toolchain/check/handle.h"
 
 namespace Carbon::Check {
@@ -22,6 +23,8 @@ auto HandleParseNode(Context& context, Parse::WhereOperandId /*node_id*/)
   // Introduce a name scope so that we can remove the `.Self` entry we are
   // adding to name lookup at the end of the `where` expression.
   context.scope_stack().Push();
+  // Create a generic region containing `.Self` and the constraints.
+  StartGenericDecl(context);
   // Introduce `.Self` as a symbolic binding. Its type is the value of the
   // expression to the left of `where`, so `MyInterface` in the example above.
   // Because there is no equivalent non-symbolic value, we use `Invalid` as
@@ -74,6 +77,9 @@ auto HandleParseNode(Context& /*context*/, Parse::RequirementAndId /*node_id*/)
 }
 
 auto HandleParseNode(Context& context, Parse::WhereExprId /*node_id*/) -> bool {
+  // Discard the generic region containing `.Self` and the constraints.
+  // TODO: Decide if we want to build a `Generic` object for this.
+  DiscardGenericDecl(context);
   // Remove `PeriodSelf` from name lookup, undoing the `Push` done for the
   // `WhereOperand`.
   context.scope_stack().Pop();

toolchain/check/testdata/where_expr/constraints.carbon

@@ -138,8 +138,8 @@ fn NotEmptyStruct() {
 // CHECK:STDOUT:     %T.patt: %.2 = symbolic_binding_pattern T 0
 // CHECK:STDOUT:   } {
 // CHECK:STDOUT:     %I.ref: type = name_ref I, file.%I.decl [template = constants.%.2]
-// CHECK:STDOUT:     %.Self.1: %.2 = bind_symbolic_name .Self 0 [symbolic = %.Self.2 (constants.%.Self.1)]
-// CHECK:STDOUT:     %.Self.ref: %.2 = name_ref .Self, %.Self.1 [symbolic = %.Self.2 (constants.%.Self.1)]
+// CHECK:STDOUT:     %.Self: %.2 = bind_symbolic_name .Self 0 [symbolic = constants.%.Self.1]
+// CHECK:STDOUT:     %.Self.ref: %.2 = name_ref .Self, %.Self [symbolic = constants.%.Self.1]
 // CHECK:STDOUT:     %Member.ref: %.3 = name_ref Member, @I.%.loc7 [template = constants.%.4]
 // CHECK:STDOUT:     %.loc11: %.8 = struct_literal ()
 // CHECK:STDOUT:     %T.param: %.2 = param T, runtime_param<invalid>
@@ -149,8 +149,8 @@ fn NotEmptyStruct() {
 // CHECK:STDOUT:     %U.patt: %.2 = symbolic_binding_pattern U 0
 // CHECK:STDOUT:   } {
 // CHECK:STDOUT:     %I.ref: type = name_ref I, file.%I.decl [template = constants.%.2]
-// CHECK:STDOUT:     %.Self.1: %.2 = bind_symbolic_name .Self 0 [symbolic = %.Self.2 (constants.%.Self.1)]
-// CHECK:STDOUT:     %.Self.ref: %.2 = name_ref .Self, %.Self.1 [symbolic = %.Self.2 (constants.%.Self.1)]
+// CHECK:STDOUT:     %.Self: %.2 = bind_symbolic_name .Self 0 [symbolic = constants.%.Self.1]
+// CHECK:STDOUT:     %.Self.ref: %.2 = name_ref .Self, %.Self [symbolic = constants.%.Self.1]
 // CHECK:STDOUT:     %.loc13: %.5 = tuple_literal ()
 // CHECK:STDOUT:     %U.param: %.2 = param U, runtime_param<invalid>
 // CHECK:STDOUT:     %U.loc13: %.2 = bind_symbolic_name U 0, %U.param [symbolic = %U.1 (constants.%U)]
@@ -159,8 +159,8 @@ fn NotEmptyStruct() {
 // CHECK:STDOUT:     %V.patt: %.1 = symbolic_binding_pattern V 0
 // CHECK:STDOUT:   } {
 // CHECK:STDOUT:     %J.ref: type = name_ref J, file.%J.decl [template = constants.%.1]
-// CHECK:STDOUT:     %.Self.1: %.1 = bind_symbolic_name .Self 0 [symbolic = %.Self.2 (constants.%.Self.2)]
-// CHECK:STDOUT:     %.Self.ref: %.1 = name_ref .Self, %.Self.1 [symbolic = %.Self.2 (constants.%.Self.2)]
+// CHECK:STDOUT:     %.Self: %.1 = bind_symbolic_name .Self 0 [symbolic = constants.%.Self.2]
+// CHECK:STDOUT:     %.Self.ref: %.1 = name_ref .Self, %.Self [symbolic = constants.%.Self.2]
 // CHECK:STDOUT:     %I.ref: type = name_ref I, file.%I.decl [template = constants.%.2]
 // CHECK:STDOUT:     %V.param: %.1 = param V, runtime_param<invalid>
 // CHECK:STDOUT:     %V.loc15: %.1 = bind_symbolic_name V 0, %V.param [symbolic = %V.1 (constants.%V)]
@@ -169,13 +169,13 @@ fn NotEmptyStruct() {
 // CHECK:STDOUT:     %W.patt: %.2 = symbolic_binding_pattern W 0
 // CHECK:STDOUT:   } {
 // CHECK:STDOUT:     %I.ref.loc17_12: type = name_ref I, file.%I.decl [template = constants.%.2]
-// CHECK:STDOUT:     %.Self.1: %.2 = bind_symbolic_name .Self 0 [symbolic = %.Self.2 (constants.%.Self.1)]
-// CHECK:STDOUT:     %.Self.ref.loc17_20: %.2 = name_ref .Self, %.Self.1 [symbolic = %.Self.2 (constants.%.Self.1)]
+// CHECK:STDOUT:     %.Self: %.2 = bind_symbolic_name .Self 0 [symbolic = constants.%.Self.1]
+// CHECK:STDOUT:     %.Self.ref.loc17_20: %.2 = name_ref .Self, %.Self [symbolic = constants.%.Self.1]
 // CHECK:STDOUT:     %Second.ref.loc17_20: %.6 = name_ref Second, @I.%.loc8 [template = constants.%.7]
 // CHECK:STDOUT:     %I.ref.loc17_34: type = name_ref I, file.%I.decl [template = constants.%.2]
-// CHECK:STDOUT:     %.Self.ref.loc17_40: %.2 = name_ref .Self, %.Self.1 [symbolic = %.Self.2 (constants.%.Self.1)]
+// CHECK:STDOUT:     %.Self.ref.loc17_40: %.2 = name_ref .Self, %.Self [symbolic = constants.%.Self.1]
 // CHECK:STDOUT:     %Member.ref: %.3 = name_ref Member, @I.%.loc7 [template = constants.%.4]
-// CHECK:STDOUT:     %.Self.ref.loc17_50: %.2 = name_ref .Self, %.Self.1 [symbolic = %.Self.2 (constants.%.Self.1)]
+// CHECK:STDOUT:     %.Self.ref.loc17_50: %.2 = name_ref .Self, %.Self [symbolic = constants.%.Self.1]
 // CHECK:STDOUT:     %Second.ref.loc17_50: %.6 = name_ref Second, @I.%.loc8 [template = constants.%.7]
 // CHECK:STDOUT:     %W.param: %.2 = param W, runtime_param<invalid>
 // CHECK:STDOUT:     %W.loc17: %.2 = bind_symbolic_name W 0, %W.param [symbolic = %W.1 (constants.%W)]
@@ -206,50 +206,42 @@ fn NotEmptyStruct() {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: generic fn @Equal(%T.loc11: %.2) {
-// CHECK:STDOUT:   %.Self.2: %.2 = bind_symbolic_name .Self 0 [symbolic = %.Self.2 (constants.%.Self.1)]
 // CHECK:STDOUT:   %T.1: %.2 = bind_symbolic_name T 0 [symbolic = %T.1 (constants.%T)]
 // CHECK:STDOUT:
 // CHECK:STDOUT:   fn(%T.loc11: %.2);
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: generic fn @EqualEqual(%U.loc13: %.2) {
-// CHECK:STDOUT:   %.Self.2: %.2 = bind_symbolic_name .Self 0 [symbolic = %.Self.2 (constants.%.Self.1)]
 // CHECK:STDOUT:   %U.1: %.2 = bind_symbolic_name U 0 [symbolic = %U.1 (constants.%U)]
 // CHECK:STDOUT:
 // CHECK:STDOUT:   fn(%U.loc13: %.2);
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: generic fn @Impls(%V.loc15: %.1) {
-// CHECK:STDOUT:   %.Self.2: %.1 = bind_symbolic_name .Self 0 [symbolic = %.Self.2 (constants.%.Self.2)]
 // CHECK:STDOUT:   %V.1: %.1 = bind_symbolic_name V 0 [symbolic = %V.1 (constants.%V)]
 // CHECK:STDOUT:
 // CHECK:STDOUT:   fn(%V.loc15: %.1);
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: generic fn @And(%W.loc17: %.2) {
-// CHECK:STDOUT:   %.Self.2: %.2 = bind_symbolic_name .Self 0 [symbolic = %.Self.2 (constants.%.Self.1)]
 // CHECK:STDOUT:   %W.1: %.2 = bind_symbolic_name W 0 [symbolic = %W.1 (constants.%W)]
 // CHECK:STDOUT:
 // CHECK:STDOUT:   fn(%W.loc17: %.2);
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: specific @Equal(constants.%T) {
-// CHECK:STDOUT:   %.Self.2 => constants.%T
 // CHECK:STDOUT:   %T.1 => constants.%T
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: specific @EqualEqual(constants.%U) {
-// CHECK:STDOUT:   %.Self.2 => constants.%U
 // CHECK:STDOUT:   %U.1 => constants.%U
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: specific @Impls(constants.%V) {
-// CHECK:STDOUT:   %.Self.2 => constants.%V
 // CHECK:STDOUT:   %V.1 => constants.%V
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: specific @And(constants.%W) {
-// CHECK:STDOUT:   %.Self.2 => constants.%W
 // CHECK:STDOUT:   %W.1 => constants.%W
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
@@ -272,9 +264,9 @@ fn NotEmptyStruct() {
 // CHECK:STDOUT:   %import_ref.1 = import_ref Main//state_constraints, inst+3, unloaded
 // CHECK:STDOUT:   %import_ref.2: type = import_ref Main//state_constraints, inst+7, loaded [template = constants.%.1]
 // CHECK:STDOUT:   %import_ref.3 = import_ref Main//state_constraints, inst+32, unloaded
-// CHECK:STDOUT:   %import_ref.4 = import_ref Main//state_constraints, inst+45, unloaded
-// CHECK:STDOUT:   %import_ref.5 = import_ref Main//state_constraints, inst+59, unloaded
-// CHECK:STDOUT:   %import_ref.6 = import_ref Main//state_constraints, inst+77, unloaded
+// CHECK:STDOUT:   %import_ref.4 = import_ref Main//state_constraints, inst+44, unloaded
+// CHECK:STDOUT:   %import_ref.5 = import_ref Main//state_constraints, inst+57, unloaded
+// CHECK:STDOUT:   %import_ref.6 = import_ref Main//state_constraints, inst+74, unloaded
 // CHECK:STDOUT:   %Core: <namespace> = namespace file.%Core.import, [template] {
 // CHECK:STDOUT:     import Core//prelude
 // CHECK:STDOUT:     import Core//prelude/operators
@@ -310,8 +302,8 @@ fn NotEmptyStruct() {
 // CHECK:STDOUT:     %X.patt: %.1 = symbolic_binding_pattern X 0
 // CHECK:STDOUT:   } {
 // CHECK:STDOUT:     %I.ref: type = name_ref I, imports.%import_ref.2 [template = constants.%.1]
-// CHECK:STDOUT:     %.Self.1: %.1 = bind_symbolic_name .Self 0 [symbolic = %.Self.2 (constants.%.Self)]
-// CHECK:STDOUT:     %.Self.ref: %.1 = name_ref .Self, %.Self.1 [symbolic = %.Self.2 (constants.%.Self)]
+// CHECK:STDOUT:     %.Self: %.1 = bind_symbolic_name .Self 0 [symbolic = constants.%.Self]
+// CHECK:STDOUT:     %.Self.ref: %.1 = name_ref .Self, %.Self [symbolic = constants.%.Self]
 // CHECK:STDOUT:     %Member.ref: %.3 = name_ref Member, imports.%import_ref.8 [template = constants.%.4]
 // CHECK:STDOUT:     %.loc8: i32 = int_literal 2 [template = constants.%.5]
 // CHECK:STDOUT:     %X.param: %.1 = param X, runtime_param<invalid>
@@ -328,14 +320,12 @@ fn NotEmptyStruct() {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: generic fn @TypeMismatch(%X.loc8: %.1) {
-// CHECK:STDOUT:   %.Self.2: %.1 = bind_symbolic_name .Self 0 [symbolic = %.Self.2 (constants.%.Self)]
 // CHECK:STDOUT:   %X.1: %.1 = bind_symbolic_name X 0 [symbolic = %X.1 (constants.%X)]
 // CHECK:STDOUT:
 // CHECK:STDOUT:   fn(%X.loc8: %.1);
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: specific @TypeMismatch(constants.%X) {
-// CHECK:STDOUT:   %.Self.2 => constants.%X
 // CHECK:STDOUT:   %X.1 => constants.%X
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
@@ -354,7 +344,6 @@ fn NotEmptyStruct() {
 // CHECK:STDOUT:   %Impls.type: type = fn_type @Impls [template]
 // CHECK:STDOUT:   %Impls: %Impls.type = struct_value () [template]
 // CHECK:STDOUT:   %V: %.3 = bind_symbolic_name V 0 [symbolic]
-// CHECK:STDOUT:   %.Self.1: %.3 = bind_symbolic_name .Self 0 [symbolic]
 // CHECK:STDOUT:   %ImplicitAs.type: type = generic_interface_type @ImplicitAs [template]
 // CHECK:STDOUT:   %ImplicitAs: %ImplicitAs.type = struct_value () [template]
 // CHECK:STDOUT:   %Dest: type = bind_symbolic_name Dest 0 [symbolic]
@@ -371,7 +360,7 @@ fn NotEmptyStruct() {
 // CHECK:STDOUT:   %.10: type = assoc_entity_type %.9, %Convert.type.2 [template]
 // CHECK:STDOUT:   %.11: %.10 = assoc_entity element0, imports.%import_ref.12 [template]
 // CHECK:STDOUT:   %.12: %.7 = assoc_entity element0, imports.%import_ref.13 [symbolic]
-// CHECK:STDOUT:   %.Self.2: %.3 = bind_symbolic_name .Self 0 [symbolic]
+// CHECK:STDOUT:   %.Self: %.3 = bind_symbolic_name .Self 0 [symbolic]
 // CHECK:STDOUT:   %Y: %.3 = bind_symbolic_name Y 0 [symbolic]
 // CHECK:STDOUT:   %EmptyStruct.type: type = fn_type @EmptyStruct [template]
 // CHECK:STDOUT:   %EmptyStruct: %EmptyStruct.type = struct_value () [template]
@@ -383,9 +372,9 @@ fn NotEmptyStruct() {
 // CHECK:STDOUT:   %import_ref.1: type = import_ref Main//state_constraints, inst+3, loaded [template = constants.%.3]
 // CHECK:STDOUT:   %import_ref.2 = import_ref Main//state_constraints, inst+7, unloaded
 // CHECK:STDOUT:   %import_ref.3 = import_ref Main//state_constraints, inst+32, unloaded
-// CHECK:STDOUT:   %import_ref.4 = import_ref Main//state_constraints, inst+45, unloaded
-// CHECK:STDOUT:   %import_ref.5: %Impls.type = import_ref Main//state_constraints, inst+59, loaded [template = constants.%Impls]
-// CHECK:STDOUT:   %import_ref.6 = import_ref Main//state_constraints, inst+77, unloaded
+// CHECK:STDOUT:   %import_ref.4 = import_ref Main//state_constraints, inst+44, unloaded
+// CHECK:STDOUT:   %import_ref.5: %Impls.type = import_ref Main//state_constraints, inst+57, loaded [template = constants.%Impls]
+// CHECK:STDOUT:   %import_ref.6 = import_ref Main//state_constraints, inst+74, unloaded
 // CHECK:STDOUT:   %Core: <namespace> = namespace file.%Core.import, [template] {
 // CHECK:STDOUT:     .ImplicitAs = %import_ref.8
 // CHECK:STDOUT:     import Core//prelude
@@ -432,8 +421,8 @@ fn NotEmptyStruct() {
 // CHECK:STDOUT:     %Y.patt: %.3 = symbolic_binding_pattern Y 0
 // CHECK:STDOUT:   } {
 // CHECK:STDOUT:     %J.ref: type = name_ref J, imports.%import_ref.1 [template = constants.%.3]
-// CHECK:STDOUT:     %.Self.1: %.3 = bind_symbolic_name .Self 0 [symbolic = %.Self.2 (constants.%.Self.2)]
-// CHECK:STDOUT:     %.Self.ref: %.3 = name_ref .Self, %.Self.1 [symbolic = %.Self.2 (constants.%.Self.2)]
+// CHECK:STDOUT:     %.Self: %.3 = bind_symbolic_name .Self 0 [symbolic = constants.%.Self]
+// CHECK:STDOUT:     %.Self.ref: %.3 = name_ref .Self, %.Self [symbolic = constants.%.Self]
 // CHECK:STDOUT:     %.loc26: %.1 = struct_literal ()
 // CHECK:STDOUT:     %Y.param: %.3 = param Y, runtime_param<invalid>
 // CHECK:STDOUT:     %Y.loc26: %.3 = bind_symbolic_name Y 0, %Y.param [symbolic = %Y.1 (constants.%Y)]
@@ -492,7 +481,6 @@ fn NotEmptyStruct() {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: generic fn @Impls(constants.%V: %.3) {
-// CHECK:STDOUT:   %.Self: %.3 = bind_symbolic_name .Self 0 [symbolic = %.Self (constants.%.Self.1)]
 // CHECK:STDOUT:   %V.2: %.3 = bind_symbolic_name V 0 [symbolic = %V.2 (constants.%V)]
 // CHECK:STDOUT:
 // CHECK:STDOUT:   fn(%V.1: %.3);
@@ -507,7 +495,6 @@ fn NotEmptyStruct() {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: generic fn @EmptyStruct(%Y.loc26: %.3) {
-// CHECK:STDOUT:   %.Self.2: %.3 = bind_symbolic_name .Self 0 [symbolic = %.Self.2 (constants.%.Self.2)]
 // CHECK:STDOUT:   %Y.1: %.3 = bind_symbolic_name Y 0 [symbolic = %Y.1 (constants.%Y)]
 // CHECK:STDOUT:
 // CHECK:STDOUT:   fn(%Y.loc26: %.3);
@@ -525,7 +512,6 @@ fn NotEmptyStruct() {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: specific @Impls(constants.%V) {
-// CHECK:STDOUT:   %.Self => constants.%V
 // CHECK:STDOUT:   %V.2 => constants.%V
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
@@ -560,7 +546,6 @@ fn NotEmptyStruct() {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: specific @EmptyStruct(constants.%Y) {
-// CHECK:STDOUT:   %.Self.2 => constants.%Y
 // CHECK:STDOUT:   %Y.1 => constants.%Y
 // CHECK:STDOUT: }
 // CHECK:STDOUT:

toolchain/check/testdata/where_expr/no_prelude/designator.carbon

@@ -120,8 +120,8 @@ class D {
 // CHECK:STDOUT:     %T.patt: %.1 = symbolic_binding_pattern T 0
 // CHECK:STDOUT:   } {
 // CHECK:STDOUT:     %I.ref: type = name_ref I, file.%I.decl [template = constants.%.1]
-// CHECK:STDOUT:     %.Self.1: %.1 = bind_symbolic_name .Self 0 [symbolic = %.Self.2 (constants.%.Self.1)]
-// CHECK:STDOUT:     %.Self.ref: %.1 = name_ref .Self, %.Self.1 [symbolic = %.Self.2 (constants.%.Self.1)]
+// CHECK:STDOUT:     %.Self: %.1 = bind_symbolic_name .Self 0 [symbolic = constants.%.Self.1]
+// CHECK:STDOUT:     %.Self.ref: %.1 = name_ref .Self, %.Self [symbolic = constants.%.Self.1]
 // CHECK:STDOUT:     %.loc8: %.4 = tuple_literal ()
 // CHECK:STDOUT:     %T.param: %.1 = param T, runtime_param<invalid>
 // CHECK:STDOUT:     %T.loc8: %.1 = bind_symbolic_name T 0, %T.param [symbolic = %T.1 (constants.%T)]
@@ -130,8 +130,8 @@ class D {
 // CHECK:STDOUT:     %U.patt: %.1 = symbolic_binding_pattern U 0
 // CHECK:STDOUT:   } {
 // CHECK:STDOUT:     %I.ref: type = name_ref I, file.%I.decl [template = constants.%.1]
-// CHECK:STDOUT:     %.Self.1: %.1 = bind_symbolic_name .Self 0 [symbolic = %.Self.2 (constants.%.Self.1)]
-// CHECK:STDOUT:     %.Self.ref: %.1 = name_ref .Self, %.Self.1 [symbolic = %.Self.2 (constants.%.Self.1)]
+// CHECK:STDOUT:     %.Self: %.1 = bind_symbolic_name .Self 0 [symbolic = constants.%.Self.1]
+// CHECK:STDOUT:     %.Self.ref: %.1 = name_ref .Self, %.Self [symbolic = constants.%.Self.1]
 // CHECK:STDOUT:     %Member.ref: %.2 = name_ref Member, @I.%.loc5 [template = constants.%.3]
 // CHECK:STDOUT:     %.loc10: %.5 = struct_literal ()
 // CHECK:STDOUT:     %U.param: %.1 = param U, runtime_param<invalid>
@@ -140,8 +140,8 @@ class D {
 // CHECK:STDOUT:   %TypeSelfImpls.decl: %TypeSelfImpls.type = fn_decl @TypeSelfImpls [template = constants.%TypeSelfImpls] {
 // CHECK:STDOUT:     %V.patt: type = symbolic_binding_pattern V 0
 // CHECK:STDOUT:   } {
-// CHECK:STDOUT:     %.Self.1: type = bind_symbolic_name .Self 0 [symbolic = %.Self.2 (constants.%.Self.2)]
-// CHECK:STDOUT:     %.Self.ref: type = name_ref .Self, %.Self.1 [symbolic = %.Self.2 (constants.%.Self.2)]
+// CHECK:STDOUT:     %.Self: type = bind_symbolic_name .Self 0 [symbolic = constants.%.Self.2]
+// CHECK:STDOUT:     %.Self.ref: type = name_ref .Self, %.Self [symbolic = constants.%.Self.2]
 // CHECK:STDOUT:     %I.ref: type = name_ref I, file.%I.decl [template = constants.%.1]
 // CHECK:STDOUT:     %V.param: type = param V, runtime_param<invalid>
 // CHECK:STDOUT:     %V.loc12: type = bind_symbolic_name V 0, %V.param [symbolic = %V.1 (constants.%V)]
@@ -160,38 +160,32 @@ class D {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: generic fn @PeriodSelf(%T.loc8: %.1) {
-// CHECK:STDOUT:   %.Self.2: %.1 = bind_symbolic_name .Self 0 [symbolic = %.Self.2 (constants.%.Self.1)]
 // CHECK:STDOUT:   %T.1: %.1 = bind_symbolic_name T 0 [symbolic = %T.1 (constants.%T)]
 // CHECK:STDOUT:
 // CHECK:STDOUT:   fn(%T.loc8: %.1);
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: generic fn @PeriodMember(%U.loc10: %.1) {
-// CHECK:STDOUT:   %.Self.2: %.1 = bind_symbolic_name .Self 0 [symbolic = %.Self.2 (constants.%.Self.1)]
 // CHECK:STDOUT:   %U.1: %.1 = bind_symbolic_name U 0 [symbolic = %U.1 (constants.%U)]
 // CHECK:STDOUT:
 // CHECK:STDOUT:   fn(%U.loc10: %.1);
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: generic fn @TypeSelfImpls(%V.loc12: type) {
-// CHECK:STDOUT:   %.Self.2: type = bind_symbolic_name .Self 0 [symbolic = %.Self.2 (constants.%.Self.2)]
 // CHECK:STDOUT:   %V.1: type = bind_symbolic_name V 0 [symbolic = %V.1 (constants.%V)]
 // CHECK:STDOUT:
 // CHECK:STDOUT:   fn(%V.loc12: type);
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: specific @PeriodSelf(constants.%T) {
-// CHECK:STDOUT:   %.Self.2 => constants.%T
 // CHECK:STDOUT:   %T.1 => constants.%T
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: specific @PeriodMember(constants.%U) {
-// CHECK:STDOUT:   %.Self.2 => constants.%U
 // CHECK:STDOUT:   %U.1 => constants.%U
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: specific @TypeSelfImpls(constants.%V) {
-// CHECK:STDOUT:   %.Self.2 => constants.%V
 // CHECK:STDOUT:   %V.1 => constants.%V
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
@@ -220,8 +214,8 @@ class D {
 // CHECK:STDOUT:     %W.patt: %.1 = symbolic_binding_pattern W 0
 // CHECK:STDOUT:   } {
 // CHECK:STDOUT:     %J.ref: type = name_ref J, file.%J.decl [template = constants.%.1]
-// CHECK:STDOUT:     %.Self.1: %.1 = bind_symbolic_name .Self 0 [symbolic = %.Self.2 (constants.%.Self)]
-// CHECK:STDOUT:     %.Self.ref: %.1 = name_ref .Self, %.Self.1 [symbolic = %.Self.2 (constants.%.Self)]
+// CHECK:STDOUT:     %.Self: %.1 = bind_symbolic_name .Self 0 [symbolic = constants.%.Self]
+// CHECK:STDOUT:     %.Self.ref: %.1 = name_ref .Self, %.Self [symbolic = constants.%.Self]
 // CHECK:STDOUT:     %Mismatch.ref: <error> = name_ref Mismatch, <error> [template = <error>]
 // CHECK:STDOUT:     %.loc12: %.5 = struct_literal ()
 // CHECK:STDOUT:     %W.param: %.1 = param W, runtime_param<invalid>
@@ -241,14 +235,12 @@ class D {
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: generic fn @PeriodMismatch(%W.loc12: %.1) {
-// CHECK:STDOUT:   %.Self.2: %.1 = bind_symbolic_name .Self 0 [symbolic = %.Self.2 (constants.%.Self)]
 // CHECK:STDOUT:   %W.1: %.1 = bind_symbolic_name W 0 [symbolic = %W.1 (constants.%W)]
 // CHECK:STDOUT:
 // CHECK:STDOUT:   fn(%W.loc12: %.1);
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: specific @PeriodMismatch(constants.%W) {
-// CHECK:STDOUT:   %.Self.2 => constants.%W
 // CHECK:STDOUT:   %W.1 => constants.%W
 // CHECK:STDOUT: }
 // CHECK:STDOUT:

toolchain/check/testdata/where_expr/no_prelude/non_generic.carbon

@@ -0,0 +1,64 @@
+// Part of the Carbon Language project, under the Apache License v2.0 with LLVM
+// Exceptions. See /LICENSE for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+// AUTOUPDATE
+// TIP: To test this file alone, run:
+// TIP:   bazel test //toolchain/testing:file_test --test_arg=--file_tests=toolchain/check/testdata/where_expr/no_prelude/non_generic.carbon
+// TIP: To dump output, run:
+// TIP:   bazel run //toolchain/testing:file_test -- --dump_output --file_tests=toolchain/check/testdata/where_expr/no_prelude/non_generic.carbon
+
+interface I { let T:! type; }
+
+// Ensure that we don't crash when checking this `where` in a non-generic context.
+fn NotGenericF(U: I where .T = {}) {}
+
+// CHECK:STDOUT: --- non_generic.carbon
+// CHECK:STDOUT:
+// CHECK:STDOUT: constants {
+// CHECK:STDOUT:   %.1: type = interface_type @I [template]
+// CHECK:STDOUT:   %Self: %.1 = bind_symbolic_name Self 0 [symbolic]
+// CHECK:STDOUT:   %.2: type = assoc_entity_type %.1, type [template]
+// CHECK:STDOUT:   %.3: %.2 = assoc_entity element0, @I.%T [template]
+// CHECK:STDOUT:   %.Self: %.1 = bind_symbolic_name .Self 0 [symbolic]
+// CHECK:STDOUT:   %.4: type = tuple_type () [template]
+// CHECK:STDOUT:   %.5: type = struct_type {} [template]
+// CHECK:STDOUT:   %NotGenericF.type: type = fn_type @NotGenericF [template]
+// CHECK:STDOUT:   %NotGenericF: %NotGenericF.type = struct_value () [template]
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: file {
+// CHECK:STDOUT:   package: <namespace> = namespace [template] {
+// CHECK:STDOUT:     .I = %I.decl
+// CHECK:STDOUT:     .NotGenericF = %NotGenericF.decl
+// CHECK:STDOUT:   }
+// CHECK:STDOUT:   %I.decl: type = interface_decl @I [template = constants.%.1] {} {}
+// CHECK:STDOUT:   %NotGenericF.decl: %NotGenericF.type = fn_decl @NotGenericF [template = constants.%NotGenericF] {
+// CHECK:STDOUT:     %U.patt: %.1 = binding_pattern U
+// CHECK:STDOUT:   } {
+// CHECK:STDOUT:     %I.ref: type = name_ref I, file.%I.decl [template = constants.%.1]
+// CHECK:STDOUT:     %.Self: %.1 = bind_symbolic_name .Self 0 [symbolic = constants.%.Self]
+// CHECK:STDOUT:     %.Self.ref: %.1 = name_ref .Self, %.Self [symbolic = constants.%.Self]
+// CHECK:STDOUT:     %T.ref: %.2 = name_ref T, @I.%.loc11 [template = constants.%.3]
+// CHECK:STDOUT:     %.loc14: %.5 = struct_literal ()
+// CHECK:STDOUT:     %U.param: %.1 = param U, runtime_param0
+// CHECK:STDOUT:     %U: %.1 = bind_name U, %U.param
+// CHECK:STDOUT:   }
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: interface @I {
+// CHECK:STDOUT:   %Self: %.1 = bind_symbolic_name Self 0 [symbolic = constants.%Self]
+// CHECK:STDOUT:   %T: type = assoc_const_decl T [template]
+// CHECK:STDOUT:   %.loc11: %.2 = assoc_entity element0, %T [template = constants.%.3]
+// CHECK:STDOUT:
+// CHECK:STDOUT: !members:
+// CHECK:STDOUT:   .Self = %Self
+// CHECK:STDOUT:   .T = %.loc11
+// CHECK:STDOUT:   witness = (%T)
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: fn @NotGenericF(%U: %.1) {
+// CHECK:STDOUT: !entry:
+// CHECK:STDOUT:   return
+// CHECK:STDOUT: }
+// CHECK:STDOUT: