Implement unused pattern bindings, continued (#6518)

Implementation of unused pattern bindings #2022, continued.

Whereas previous PR #6460 took care of parsing, and PR #6479 prepared
the stage by using _ in some test cases, this PR has the the actual
implementation, using a simple dataflow analysis.

---------

Co-authored-by: Burak Emir <bqe@google.com>
Co-authored-by: jonmeow <jperkins@google.com>
This commit is contained in:
Burak Emir
2026-02-19 23:33:36 +00:00
committed by GitHub
co-authored by Burak Emir jonmeow
parent bea24a8bee
commit fdb188ccfd
366 changed files with 8453 additions and 7996 deletions
+27 -27
View File
@@ -24,8 +24,8 @@ import Cpp library "enum.h";
//@dump-sem-ir-begin
fn F() {
let a: Cpp.Enum = Cpp.Enum.a;
let b: Cpp.Enum = Cpp.b;
let unused a: Cpp.Enum = Cpp.Enum.a;
let unused b: Cpp.Enum = Cpp.b;
}
//@dump-sem-ir-end
@@ -36,23 +36,23 @@ library "[[@TEST_NAME]]";
import Cpp library "enum.h";
fn F() {
// CHECK:STDERR: fail_wrong_enum.carbon:[[@LINE+7]]:22: error: cannot implicitly convert expression of type `Cpp.Enum` to `Cpp.Other` [ConversionFailure]
// CHECK:STDERR: let c: Cpp.Other = Cpp.Enum.c;
// CHECK:STDERR: ^~~~~~~~~~
// CHECK:STDERR: fail_wrong_enum.carbon:[[@LINE+4]]:22: note: type `Cpp.Enum` does not implement interface `Core.ImplicitAs(Cpp.Other)` [MissingImplInMemberAccessNote]
// CHECK:STDERR: let c: Cpp.Other = Cpp.Enum.c;
// CHECK:STDERR: ^~~~~~~~~~
// CHECK:STDERR: fail_wrong_enum.carbon:[[@LINE+7]]:29: error: cannot implicitly convert expression of type `Cpp.Enum` to `Cpp.Other` [ConversionFailure]
// CHECK:STDERR: let unused c: Cpp.Other = Cpp.Enum.c;
// CHECK:STDERR: ^~~~~~~~~~
// CHECK:STDERR: fail_wrong_enum.carbon:[[@LINE+4]]:29: note: type `Cpp.Enum` does not implement interface `Core.ImplicitAs(Cpp.Other)` [MissingImplInMemberAccessNote]
// CHECK:STDERR: let unused c: Cpp.Other = Cpp.Enum.c;
// CHECK:STDERR: ^~~~~~~~~~
// CHECK:STDERR:
let c: Cpp.Other = Cpp.Enum.c;
let unused c: Cpp.Other = Cpp.Enum.c;
// CHECK:STDERR: fail_wrong_enum.carbon:[[@LINE+7]]:23: error: cannot implicitly convert expression of type `Cpp.Enum` to `Cpp.Other` [ConversionFailure]
// CHECK:STDERR: let c2: Cpp.Other = Cpp.c;
// CHECK:STDERR: ^~~~~
// CHECK:STDERR: fail_wrong_enum.carbon:[[@LINE+4]]:23: note: type `Cpp.Enum` does not implement interface `Core.ImplicitAs(Cpp.Other)` [MissingImplInMemberAccessNote]
// CHECK:STDERR: let c2: Cpp.Other = Cpp.c;
// CHECK:STDERR: ^~~~~
// CHECK:STDERR: fail_wrong_enum.carbon:[[@LINE+7]]:30: error: cannot implicitly convert expression of type `Cpp.Enum` to `Cpp.Other` [ConversionFailure]
// CHECK:STDERR: let unused c2: Cpp.Other = Cpp.c;
// CHECK:STDERR: ^~~~~
// CHECK:STDERR: fail_wrong_enum.carbon:[[@LINE+4]]:30: note: type `Cpp.Enum` does not implement interface `Core.ImplicitAs(Cpp.Other)` [MissingImplInMemberAccessNote]
// CHECK:STDERR: let unused c2: Cpp.Other = Cpp.c;
// CHECK:STDERR: ^~~~~
// CHECK:STDERR:
let c2: Cpp.Other = Cpp.c;
let unused c2: Cpp.Other = Cpp.c;
}
// --- fail_non_enum_member.carbon
@@ -62,11 +62,11 @@ library "[[@TEST_NAME]]";
import Cpp library "enum.h";
fn F() {
// CHECK:STDERR: fail_non_enum_member.carbon:[[@LINE+4]]:22: error: member name `d` not found in `Cpp.Enum` [MemberNameNotFoundInInstScope]
// CHECK:STDERR: let c: Cpp.Other = Cpp.Enum.d;
// CHECK:STDERR: ^~~~~~~~~~
// CHECK:STDERR: fail_non_enum_member.carbon:[[@LINE+4]]:29: error: member name `d` not found in `Cpp.Enum` [MemberNameNotFoundInInstScope]
// CHECK:STDERR: let unused c: Cpp.Other = Cpp.Enum.d;
// CHECK:STDERR: ^~~~~~~~~~
// CHECK:STDERR:
let c: Cpp.Other = Cpp.Enum.d;
let unused c: Cpp.Other = Cpp.Enum.d;
}
// CHECK:STDOUT: --- import_enum.carbon
@@ -100,21 +100,21 @@ fn F() {
// CHECK:STDOUT: name_binding_decl {
// CHECK:STDOUT: %a.patt: %pattern_type = value_binding_pattern a [concrete]
// CHECK:STDOUT: }
// CHECK:STDOUT: %Cpp.ref.loc8_21: <namespace> = name_ref Cpp, imports.%Cpp [concrete = imports.%Cpp]
// CHECK:STDOUT: %Enum.ref.loc8_24: type = name_ref Enum, imports.%Enum.decl [concrete = constants.%Enum]
// CHECK:STDOUT: %Cpp.ref.loc8_28: <namespace> = name_ref Cpp, imports.%Cpp [concrete = imports.%Cpp]
// CHECK:STDOUT: %Enum.ref.loc8_31: type = name_ref Enum, imports.%Enum.decl [concrete = constants.%Enum]
// CHECK:STDOUT: %a.ref: %Enum = name_ref a, imports.%int_0 [concrete = constants.%int_0]
// CHECK:STDOUT: %.loc8: type = splice_block %Enum.ref.loc8_13 [concrete = constants.%Enum] {
// CHECK:STDOUT: %Cpp.ref.loc8_10: <namespace> = name_ref Cpp, imports.%Cpp [concrete = imports.%Cpp]
// CHECK:STDOUT: %Enum.ref.loc8_13: type = name_ref Enum, imports.%Enum.decl [concrete = constants.%Enum]
// CHECK:STDOUT: %.loc8: type = splice_block %Enum.ref.loc8_20 [concrete = constants.%Enum] {
// CHECK:STDOUT: %Cpp.ref.loc8_17: <namespace> = name_ref Cpp, imports.%Cpp [concrete = imports.%Cpp]
// CHECK:STDOUT: %Enum.ref.loc8_20: type = name_ref Enum, imports.%Enum.decl [concrete = constants.%Enum]
// CHECK:STDOUT: }
// CHECK:STDOUT: %a: %Enum = value_binding a, %a.ref
// CHECK:STDOUT: name_binding_decl {
// CHECK:STDOUT: %b.patt: %pattern_type = value_binding_pattern b [concrete]
// CHECK:STDOUT: }
// CHECK:STDOUT: %Cpp.ref.loc9_21: <namespace> = name_ref Cpp, imports.%Cpp [concrete = imports.%Cpp]
// CHECK:STDOUT: %Cpp.ref.loc9_28: <namespace> = name_ref Cpp, imports.%Cpp [concrete = imports.%Cpp]
// CHECK:STDOUT: %b.ref: %Enum = name_ref b, imports.%int_1 [concrete = constants.%int_1]
// CHECK:STDOUT: %.loc9: type = splice_block %Enum.ref.loc9 [concrete = constants.%Enum] {
// CHECK:STDOUT: %Cpp.ref.loc9_10: <namespace> = name_ref Cpp, imports.%Cpp [concrete = imports.%Cpp]
// CHECK:STDOUT: %Cpp.ref.loc9_17: <namespace> = name_ref Cpp, imports.%Cpp [concrete = imports.%Cpp]
// CHECK:STDOUT: %Enum.ref.loc9: type = name_ref Enum, imports.%Enum.decl [concrete = constants.%Enum]
// CHECK:STDOUT: }
// CHECK:STDOUT: %b: %Enum = value_binding b, %b.ref