cmd/link: put shlib ".type" functions in internal ABI
These functions are compiler generated, and as such are only available
in the internal ABI. Doing this avoids generating an alias symbol.
Doing that avoids confusion between unmangled and mangled type symbols.
Fixes #30768
Change-Id: I197a5ba6403aac11989ffa951dbe35bd0506de91
Reviewed-on: https://go-review.googlesource.com/c/go/+/186077
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
diff --git a/misc/cgo/testshared/shared_test.go b/misc/cgo/testshared/shared_test.go
index ac1a1c7..9d16338 100644
--- a/misc/cgo/testshared/shared_test.go
+++ b/misc/cgo/testshared/shared_test.go
@@ -941,3 +941,10 @@
func TestGeneratedMethod(t *testing.T) {
goCmd(t, "install", "-buildmode=shared", "-linkshared", "./issue25065")
}
+
+// Test use of shared library struct with generated hash function.
+// Issue 30768.
+func TestGeneratedHash(t *testing.T) {
+ goCmd(nil, "install", "-buildmode=shared", "-linkshared", "./issue30768/issue30768lib")
+ goCmd(nil, "test", "-linkshared", "./issue30768")
+}
diff --git a/misc/cgo/testshared/testdata/issue30768/issue30768lib/lib.go b/misc/cgo/testshared/testdata/issue30768/issue30768lib/lib.go
new file mode 100644
index 0000000..9e45ebe
--- /dev/null
+++ b/misc/cgo/testshared/testdata/issue30768/issue30768lib/lib.go
@@ -0,0 +1,11 @@
+// Copyright 2019 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 issue30768lib
+
+// S is a struct that requires a generated hash function.
+type S struct {
+ A string
+ B int
+}
diff --git a/misc/cgo/testshared/testdata/issue30768/x_test.go b/misc/cgo/testshared/testdata/issue30768/x_test.go
new file mode 100644
index 0000000..1bbd139
--- /dev/null
+++ b/misc/cgo/testshared/testdata/issue30768/x_test.go
@@ -0,0 +1,22 @@
+// Copyright 2019 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 issue30768_test
+
+import (
+ "testing"
+
+ "testshared/issue30768/issue30768lib"
+)
+
+type s struct {
+ s issue30768lib.S
+}
+
+func Test30768(t *testing.T) {
+ // Calling t.Log will convert S to an empty interface,
+ // which will force a reference to the generated hash function,
+ // defined in the shared library.
+ t.Log(s{})
+}
diff --git a/src/cmd/link/internal/ld/lib.go b/src/cmd/link/internal/ld/lib.go
index 49f3b3c..9c71a4f 100644
--- a/src/cmd/link/internal/ld/lib.go
+++ b/src/cmd/link/internal/ld/lib.go
@@ -1902,7 +1902,15 @@
if elf.ST_TYPE(elfsym.Info) == elf.STT_NOTYPE || elf.ST_TYPE(elfsym.Info) == elf.STT_SECTION {
continue
}
- lsym := ctxt.Syms.Lookup(elfsym.Name, 0)
+
+ // Symbols whose names start with "type." are compiler
+ // generated, so make functions with that prefix internal.
+ ver := 0
+ if elf.ST_TYPE(elfsym.Info) == elf.STT_FUNC && strings.HasPrefix(elfsym.Name, "type.") {
+ ver = sym.SymVerABIInternal
+ }
+
+ lsym := ctxt.Syms.Lookup(elfsym.Name, ver)
// Because loadlib above loads all .a files before loading any shared
// libraries, any non-dynimport symbols we find that duplicate symbols
// already loaded should be ignored (the symbols from the .a files
@@ -1930,7 +1938,7 @@
// the ABIs are actually different. We might have to
// mangle Go function names in the .so to include the
// ABI.
- if elf.ST_TYPE(elfsym.Info) == elf.STT_FUNC {
+ if elf.ST_TYPE(elfsym.Info) == elf.STT_FUNC && ver == 0 {
alias := ctxt.Syms.Lookup(elfsym.Name, sym.SymVerABIInternal)
if alias.Type != 0 {
continue
