make 5l ignore multiple defs, remove use of multiple

        defs from embed1 and gotest

R=rsc
http://go/go-review/1014009

src/cmd/5l/obj.c

@@ -432,9 +432,11 @@ ldobj1(Biobuf *f, int64 len, char *pn)
 	int v, o, r, skip;
 	uint32 sig;
 	char *name;
+	int ntext;
 	int32 eof;
 	char src[1024];
 
+	ntext = 0;
 	eof = Boffset(f) + len;
 	di = S;
 	src[0] = 0;
@@ -657,6 +659,13 @@ loop:
 		break;
 
 	case ATEXT:
+		s = p->from.sym;
+		if(ntext++ == 0 && s->type != 0 && s->type != SXREF) {
+			/* redefinition, so file has probably been seen before */
+			if(debug['v'])
+				Bprint(&bso, "skipping: %s: redefinition: %s", pn, s->name);
+			return;
+		}
 		setarch(p);
 		setthumb(p);
 		p->align = 4;

src/cmd/gotest/gotest

@@ -22,6 +22,12 @@ nacl)
 	E="nacl"
 esac
 
+# TODO(kaib): proper emulator strategy
+case x"$GOARCH" in
+xarm)
+	E="qemu-arm -cpu cortex-a8"
+esac
+
 # Allow overrides
 GC=${_GC:-$GC}
 GL=${GL:-$LD}
@@ -131,5 +137,5 @@ importpath=$(make -s importpath)
 }>_testmain.go
 
 $GC _testmain.go
-$GL _testmain.$O _test/$importpath.a $xofile
+$GL _testmain.$O
 $E ./$O.out "$@"

test/interface/embed1.go

-// $G $D/embed0.go && $G $D/$F.go && $L embed0.$A $F.$A && ./$A.out
+// $G $D/embed0.go && $G $D/$F.go && $L $F.$A && ./$A.out
 
 // Copyright 2009 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style