diff --git a/src/cmd/6l/obj.c b/src/cmd/6l/obj.c
index bc7413fe159..9777cdf42aa 100644
--- a/src/cmd/6l/obj.c
+++ b/src/cmd/6l/obj.c
@@ -542,6 +542,10 @@ objfile(char *file)
 				goto bad;
 			if(strncmp(arhdr.fmag, ARFMAG, sizeof(arhdr.fmag)))
 				goto bad;
+			l = SARNAME;
+			while(l > 0 && arhdr.name[l-1] == ' ')
+				l--;
+			sprint(pname, "%s(%.*s)", file, l, arhdr.name);
 			l = atolwhex(arhdr.size);
 			ldobj(f, l, pname);
 			if(s->type == SXREF) {
@@ -635,9 +639,9 @@ zaddr(Biobuf *f, Adr *a, Sym *h[])
 }
 
 void
-addlib(char *obj)
+addlib(char *src, char *obj)
 {
-	char name[1024], comp[256], *p;
+	char name[1024], comp[256], *p, *q;
 	int i;
 
 	if(histfrogp <= 0)
@@ -685,6 +689,23 @@ addlib(char *obj)
 		strcat(name, "/");
 		strcat(name, comp);
 	}
+	if(debug['v'])
+		Bprint(&bso, "%5.2f addlib: %s %s pulls in %s\n", cputime(), obj, src, name);
+
+	p = strrchr(src, '/');
+	q = strrchr(name, '/');
+	if(p != nil && q != nil && p - src == q - name && memcmp(src, name, p - src) == 0) {
+		// leading paths are the same.
+		// if the source file refers to an object in its own directory
+		// and we are inside an archive, ignore the reference, in the hope
+		// that the archive contains that object too.
+		if(strchr(obj, '(')) {
+			if(debug['v'])
+				Bprint(&bso, "%5.2f ignored srcdir object %s\n", cputime(), name);
+			return;
+		}
+	}
+
 	for(i=0; i<libraryp; i++)
 		if(strcmp(name, library[i]) == 0)
 			return;
@@ -702,6 +723,22 @@ addlib(char *obj)
 	libraryp++;
 }
 
+void
+copyhistfrog(char *buf, int nbuf)
+{
+	char *p, *ep;
+	int i;
+
+	p = buf;
+	ep = buf + nbuf;
+	i = 0;
+	for(i=0; i<histfrogp; i++) {
+		p = seprint(p, ep, "%s", histfrog[i]->name+1);
+		if(i+1<histfrogp && (p == buf || p[-1] != '/'))
+			p = seprint(p, ep, "/");
+	}
+}
+
 void
 addhist(int32 line, int type)
 {
@@ -800,7 +837,9 @@ ldobj(Biobuf *f, int64 len, char *pn)
 	int ntext, n, c1, c2, c3;
 	vlong eof;
 	vlong import0, import1;
+	char src[1024];
 
+	src[0] = '\0';
 	eof = Boffset(f) + len;
 
 	ntext = 0;
@@ -938,10 +977,12 @@ loop:
 	switch(p->as) {
 	case AHISTORY:
 		if(p->to.offset == -1) {
-			addlib(pn);
+			addlib(src, pn);
 			histfrogp = 0;
 			goto loop;
 		}
+		if(src[0] == '\0')
+			copyhistfrog(src, sizeof src);
 		addhist(p->line, D_FILE);		/* 'z' */
 		if(p->to.offset)
 			addhist(p->to.offset, D_FILE1);	/* 'Z' */
diff --git a/src/cmd/ar/ar.c b/src/cmd/ar/ar.c
index cb6ae6d442a..513d6af436c 100644
--- a/src/cmd/ar/ar.c
+++ b/src/cmd/ar/ar.c
@@ -1671,6 +1671,12 @@ getpkgdef(char **datap, int *lenp)
 	char *data, *p;
 	Import **all, *x;
 
+	if(pkgstmt == nil) {
+		*datap = nil;
+		*lenp = 0;
+		return;
+	}
+
 	// make a list of all the exports and count string sizes
 	all = armalloc(nimport*sizeof all[0]);
 	j = 0;
diff --git a/src/cmd/gobuild/gobuild.c b/src/cmd/gobuild/gobuild.c
index 56c044e9665..3a37cfd7c5f 100644
--- a/src/cmd/gobuild/gobuild.c
+++ b/src/cmd/gobuild/gobuild.c
@@ -52,6 +52,8 @@ run(char **argv, int showoutput)
 		if(!showoutput){
 			dup(devnull, 1);
 			dup(devnull, 2);
+		}else{
+			dup(2, 1);
 		}
 		if(devnull > 2)
 			close(devnull);
@@ -173,15 +175,17 @@ char preamble[] =
 	"AS=$(O)a\n"
 	"AR=$(O)ar\n"
 	"\n"
-	"PKG=$(GOROOT)/pkg/%s.a\n"
+	"PKG=%s.a\n"
+	"PKGDIR=$(GOROOT)/pkg%s\n"
 	"\n"
 	"install: $(PKG)\n"
+	"\tmv $(PKG) $(PKGDIR)/$(PKG)\n"
 	"\n"
 	"nuke: clean\n"
-	"\trm -f $(PKG)\n"
+	"\trm -f $(PKGDIR)/$(PKG)\n"
 	"\n"
 	"clean:\n"
-	"\trm -f *.$O *.a\n"
+	"\trm -f *.$O *.a $(PKG)\n"
 	"\n"
 	"%%.$O: %%.go\n"
 	"\t$(GC) $*.go\n"
@@ -198,7 +202,7 @@ void
 main(int argc, char **argv)
 {
 	int i, o, p, n, pass, nar, njob, nthis, nnext, oargc;
-	char **ar, **next, **this, **tmp, *goroot, *pkgname, *pkgpath, **oargv;
+	char **ar, **next, **this, **tmp, *goroot, *pkgname, *pkgpath, *pkgdir, **oargv, *q;
 	Job *job;
 	Biobuf bout;
 
@@ -241,7 +245,17 @@ main(int argc, char **argv)
 		usage();
 	}
 
-	pkgpath = smprint("%s/pkg/%s.a", goroot, pkgname);
+	q = strrchr(pkgname, '/');
+	if(q) {
+		pkgdir = pkgname;
+		*q++ = '\0';
+		pkgname = q;
+		pkgdir = smprint("/%s", pkgdir);
+	} else {
+		pkgdir = "";
+	}
+
+	pkgpath = smprint("%s.a", pkgname);
 	unlink(pkgpath);
 	if(chatty)
 		fprint(2, "pkg %s\n", pkgpath);
@@ -275,6 +289,9 @@ main(int argc, char **argv)
 	ar[0] = smprint("%sar", thechar);
 	ar[1] = "grc";
 	ar[2] = pkgpath;
+	ar[3] = nil;
+	if(run(ar, 1) < 0)
+		sysfatal("ar: %r");
 
 	njob = 0;
 
@@ -333,7 +350,7 @@ main(int argc, char **argv)
 			Bprint(&bout, " %s", oargv[i]);
 		}
 		Bprint(&bout, "\n");
-		Bprint(&bout, preamble, thechar, pkgname);
+		Bprint(&bout, preamble, thechar, pkgname, pkgdir);
 
 		// O2=\
 		//	os_file.$O\
diff --git a/src/lib/math/Makefile b/src/lib/math/Makefile
index c792a8eb1a5..a64d7b34a01 100644
--- a/src/lib/math/Makefile
+++ b/src/lib/math/Makefile
@@ -12,15 +12,17 @@ CC=$(O)c -w
 AS=$(O)a
 AR=$(O)ar
 
-PKG=$(GOROOT)/pkg/math.a
+PKG=math.a
+PKGDIR=$(GOROOT)/pkg
 
 install: $(PKG)
+	mv $(PKG) $(PKGDIR)/$(PKG)
 
 nuke: clean
-	rm -f $(PKG)
+	rm -f $(PKGDIR)/$(PKG)
 
 clean:
-	rm -f *.$O *.a
+	rm -f *.$O *.a $(PKG)
 
 %.$O: %.go
 	$(GC) $*.go
@@ -59,12 +61,16 @@ O4=\
 $(PKG): a1 a2 a3 a4
 a1:	$(O1)
 	$(AR) grc $(PKG) $(O1)
+	rm -f $(O1)
 a2:	$(O2)
 	$(AR) grc $(PKG) $(O2)
+	rm -f $(O2)
 a3:	$(O3)
 	$(AR) grc $(PKG) $(O3)
+	rm -f $(O3)
 a4:	$(O4)
 	$(AR) grc $(PKG) $(O4)
+	rm -f $(O4)
 
 $(O1): nuke
 $(O2): a1
diff --git a/test/math.go b/test/mathtest.go
similarity index 97%
rename from test/math.go
rename to test/mathtest.go
index e24421e8809..acfb9bab72f 100644
--- a/test/math.go
+++ b/test/mathtest.go
@@ -2,10 +2,14 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// $G $F.go && $L $F.$A && (./$A.out || echo BUG: math fails)
 
 package main
 
-import math "math"
+import (
+	"fmt";
+	"math";
+)
 
 const	length	= 10;
 
@@ -57,7 +61,7 @@ ck(a,b float64)
 		d = -d;
 	}
 
-	e := 1e-14;
+	e := float64(1e-13);
 	if a != 0 {
 		e = e*a;
 		if e < 0 {
@@ -66,7 +70,7 @@ ck(a,b float64)
 	}
 
 	if d > e {
-		panic(a, " ", b, "\n");
+		panic(fmt.sprintf("%.17g %.17g", a, b));
 	}
 }