From: Keith Randall <khr@golang.org>
Date: Wed, 6 Aug 2025 16:21:41 +0000 (-0700)
Subject: cmd/compile: allow more args in StructMake folding rule
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=72e8237cc11569de2faf9885a1b83d06446533b5;p=gostls13.git

cmd/compile: allow more args in StructMake folding rule

imakeOfStructMake does the right thing, but we never call it
when the StructMake has more than one argument.

Fixes #74908

Change-Id: Ib4b1a025bfb1fa69a325207e47b74bd6217092bf
Reviewed-on: https://go-review.googlesource.com/c/go/+/693615
Auto-Submit: Keith Randall <khr@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Keith Randall <khr@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
---

diff --git a/src/cmd/compile/internal/ssa/_gen/generic.rules b/src/cmd/compile/internal/ssa/_gen/generic.rules
index 8f354e977f..793f0a4fb6 100644
--- a/src/cmd/compile/internal/ssa/_gen/generic.rules
+++ b/src/cmd/compile/internal/ssa/_gen/generic.rules
@@ -921,7 +921,7 @@
   @x.Block (Load <v.Type> (OffPtr <v.Type.PtrTo()> [t.FieldOff(int(i))] ptr) mem)
 
 // Putting struct{*byte} and similar into direct interfaces.
-(IMake _typ (StructMake val)) => imakeOfStructMake(v)
+(IMake _typ (StructMake ___)) => imakeOfStructMake(v)
 (StructSelect [_] (IData x)) => (IData x)
 
 // un-SSAable values use mem->mem copies
diff --git a/src/cmd/compile/internal/ssa/rewritegeneric.go b/src/cmd/compile/internal/ssa/rewritegeneric.go
index 83be129a7b..adc4984b6f 100644
--- a/src/cmd/compile/internal/ssa/rewritegeneric.go
+++ b/src/cmd/compile/internal/ssa/rewritegeneric.go
@@ -11200,10 +11200,10 @@ func rewriteValuegeneric_OpFloor(v *Value) bool {
 func rewriteValuegeneric_OpIMake(v *Value) bool {
 	v_1 := v.Args[1]
 	v_0 := v.Args[0]
-	// match: (IMake _typ (StructMake val))
+	// match: (IMake _typ (StructMake ___))
 	// result: imakeOfStructMake(v)
 	for {
-		if v_1.Op != OpStructMake || len(v_1.Args) != 1 {
+		if v_1.Op != OpStructMake {
 			break
 		}
 		v.copyOf(imakeOfStructMake(v))
diff --git a/test/fixedbugs/issue74908.go b/test/fixedbugs/issue74908.go
new file mode 100644
index 0000000000..66e26d32a1
--- /dev/null
+++ b/test/fixedbugs/issue74908.go
@@ -0,0 +1,25 @@
+// compile
+
+// Copyright 2025 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+type Type struct {
+	any
+}
+
+type typeObject struct {
+	e struct{}
+	b *byte
+}
+
+func f(b *byte) Type {
+	return Type{
+		typeObject{
+			b: b,
+		},
+	}
+
+}