Commit `5d99e5ecd4`

Veikka Tuominen <git@vexu.eu>

2022-07-26 13:04:59

Sema: improve expression value ignored error

Closes #4483

master

1 parent 3d18c8c

Changed files (7)

src

Sema.zig

test

cases

compile_errors

ignored_assert-err-ok_return_value.zig

ignored_comptime_statement_value.zig

ignored_comptime_value.zig

ignored_deferred_statement_value.zig

ignored_return_value.zig

ignored_statement_value.zig

@@ -2869,7 +2869,16 @@ fn ensureResultUsed(
             };
             return sema.failWithOwnedErrorMsg(block, msg);
         },
-        else => return sema.fail(block, src, "expression value is ignored", .{}),
+        else => {
+            const msg = msg: {
+                const msg = try sema.errMsg(block, src, "value of type '{}' ignored", .{operand_ty.fmt(sema.mod)});
+                errdefer msg.destroy(sema.gpa);
+                try sema.errNote(block, src, msg, "all non-void values must be used", .{});
+                try sema.errNote(block, src, msg, "this error can be suppressed by assigning the value to '_'", .{});
+                break :msg msg;
+            };
+            return sema.failWithOwnedErrorMsg(block, msg);
+        },
     }
 }

@@ -7,4 +7,6 @@ fn bar() anyerror!i32 { return 0; }
 // backend=stage2
 // target=native
 //
-// :2:11: error: expression value is ignored
+// :2:11: error: value of type 'i32' ignored
+// :2:11: note: all non-void values must be used
+// :2:11: note: this error can be suppressed by assigning the value to '_'

@@ -6,4 +6,6 @@ export fn foo() void {
 // backend=stage2
 // target=native
 //
-// :2:15: error: expression value is ignored
+// :2:15: error: value of type 'comptime_int' ignored
+// :2:15: note: all non-void values must be used
+// :2:15: note: this error can be suppressed by assigning the value to '_'

@@ -6,4 +6,6 @@ export fn foo() void {
 // backend=stage2
 // target=native
 //
-// :2:5: error: expression value is ignored
+// :2:5: error: value of type 'comptime_int' ignored
+// :2:5: note: all non-void values must be used
+// :2:5: note: this error can be suppressed by assigning the value to '_'

@@ -6,4 +6,6 @@ export fn foo() void {
 // backend=stage2
 // target=native
 //
-// :2:12: error: expression value is ignored
+// :2:12: error: value of type 'comptime_int' ignored
+// :2:12: note: all non-void values must be used
+// :2:12: note: this error can be suppressed by assigning the value to '_'

@@ -7,4 +7,6 @@ fn bar() i32 { return 0; }
 // backend=stage2
 // target=native
 //
-// :2:8: error: expression value is ignored
+// :2:8: error: value of type 'i32' ignored
+// :2:8: note: all non-void values must be used
+// :2:8: note: this error can be suppressed by assigning the value to '_'

@@ -6,4 +6,6 @@ export fn foo() void {
 // backend=stage2
 // target=native
 //
-// :2:5: error: expression value is ignored
+// :2:5: error: value of type 'comptime_int' ignored
+// :2:5: note: all non-void values must be used
+// :2:5: note: this error can be suppressed by assigning the value to '_'

Commit 5d99e5ecd4

Commit `5d99e5ecd4`