libgo patch committed: for libffi, treat direct-iface types as pointers

[Ian Lance Taylor]

This libgo patch tweaks the libffi interface to treat direct-iface
types as pointers.  This only matters on systems that pass a struct
with a single pointer field differently than passing a single pointer.
I noticed it on 32-bit PPC, where the reflect package
TestDirectIfaceMethod failed.  Bootstrapped and ran Go testsuite on
x86_64-pc-linux-gnu.  Bootstrapped and ran some Go tests on
sparc-sun-solaris2.11 and powerpc64-linux-gnu.  Committed to mainline.

Ian

Index: gcc/go/gofrontend/MERGE
===================================================================
--- gcc/go/gofrontend/MERGE     (revision 275813)
+++ gcc/go/gofrontend/MERGE     (working copy)
@@ -1,4 +1,4 @@
-7aabaf8623cf88e2378057476a034093abbe5aab
+09ca3c1ea8a52b5d3d6c4331c59d44e0b6bfab57
 
 The first line of this file holds the git revision number of the last
 merge done from the gofrontend repository.
Index: libgo/go/runtime/ffi.go
===================================================================
--- libgo/go/runtime/ffi.go     (revision 275698)
+++ libgo/go/runtime/ffi.go     (working copy)
@@ -224,6 +224,9 @@ func structToFFI(typ *structtype) *__ffi
        if c == 0 {
                return emptyStructToFFI()
        }
+       if typ.typ.kind&kindDirectIface != 0 {
+               return ffi_type_pointer()
+       }
 
        fields := make([]*__ffi_type, 0, c+1)
        checkPad := false
@@ -307,6 +310,9 @@ func arrayToFFI(typ *arraytype) *__ffi_t
        if typ.len == 0 {
                return emptyStructToFFI()
        }
+       if typ.typ.kind&kindDirectIface != 0 {
+               return ffi_type_pointer()
+       }
        elements := make([]*__ffi_type, typ.len+1)
        et := typeToFFI(typ.elem)
        for i := uintptr(0); i < typ.len; i++ {