diff --git a/src/cmd/go/testdata/script/build_runtime_gcflags.txt b/src/cmd/go/testdata/script/build_runtime_gcflags.txt
index dc0767c569..767b768b82 100644
--- a/src/cmd/go/testdata/script/build_runtime_gcflags.txt
+++ b/src/cmd/go/testdata/script/build_runtime_gcflags.txt
@@ -1,4 +1,8 @@
-# This test verifies the standard library (specifically runtime/internal/atomic)
-# can be built with -gcflags when -n is given. See golang.org/issue/26092.
+# Set up fresh GOCACHE.
+env GOCACHE=$WORK/gocache
+mkdir $GOCACHE
+
+# Verify the standard library (specifically runtime/internal/atomic) can be
+# built with -gcflags when -n is given. See golang.org/issue/29346.
 go build -n -gcflags=all='-l' std
 stderr 'compile.* -l .* runtime/internal/atomic'