misc/cgo: re-enable some tests

The testso directory still needs to be enabled.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/5731048

src/cmd/dist/build.c

diff --git a/src/cmd/dist/build.c b/src/cmd/dist/build.c
index acd7347..6bcc0f5 100644
--- a/src/cmd/dist/build.c
+++ b/src/cmd/dist/build.c
@@ -52,6 +52,19 @@
 	"windows",
 };
 
+// The known cgo-enabled combinations.
+// This list is also known to ../../pkg/go/build/build.go.
+static char *okcgo[] = {
+	"darwin/386",
+	"darwin/amd64",
+	"linux/386",
+	"linux/amd64",
+	"freebsd/386",
+	"freebsd/amd64",
+	"windows/386",
+	"windows/amd64",
+};
+
 static void rmworkdir(void);
 
 // find reports the first index of p in l[0:n], or else -1.
@@ -1308,6 +1321,11 @@
 	xprintf(format, "GOTOOLDIR", tooldir);
 	xprintf(format, "GOCHAR", gochar);
 
+	if(find(bprintf(&b, "%s/%s", goos, goarch), okcgo, nelem(okcgo)))
+		xprintf(format, "CGO_ENABLED", "1");
+	else
+		xprintf(format, "CGO_ENABLED", "0");
+
 	if(pflag) {
 		sep = ":";
 		if(streq(gohostos, "windows"))

src/pkg/go/build/build.go

diff --git a/src/pkg/go/build/build.go b/src/pkg/go/build/build.go
index d986f80..7f7bd18 100644
--- a/src/pkg/go/build/build.go
+++ b/src/pkg/go/build/build.go
@@ -210,6 +210,7 @@
 // if set, or else the compiled code's GOARCH, GOOS, and GOROOT.
 var Default Context = defaultContext()
 
+// This list is also known to ../../../cmd/dist/build.c.
 var cgoEnabled = map[string]bool{
 	"darwin/386":    true,
 	"darwin/amd64":  true,

src/run.bash

diff --git a/src/run.bash b/src/run.bash
index 7b185486..b5ffaa9 100755
--- a/src/run.bash
+++ b/src/run.bash
@@ -35,32 +35,26 @@
 
 xcd() {
 	echo
-	echo --- cd $1
+	echo '#' $1
 	builtin cd "$GOROOT"/src/$1
 }
 
 BROKEN=true
 
-$BROKEN ||
 [ "$CGO_ENABLED" != 1 ] ||
 [ "$GOHOSTOS" == windows ] ||
 (xcd ../misc/cgo/stdio
-"$GOMAKE" clean
 ./test.bash
 ) || exit $?
 
-$BROKEN ||
 [ "$CGO_ENABLED" != 1 ] ||
 (xcd ../misc/cgo/life
-"$GOMAKE" clean
 ./test.bash
 ) || exit $?
 
-$BROKEN ||
 [ "$CGO_ENABLED" != 1 ] ||
 (xcd ../misc/cgo/test
-"$GOMAKE" clean
-gotest
+go test
 ) || exit $?
 
 $BROKEN ||