From b41adbd9c2cbf1f14f5accdb62395fa5f3fad576 Mon Sep 17 00:00:00 2001
From: Sam Alba <sam.alba@gmail.com>
Date: Wed, 9 Jun 2021 15:21:30 +0200
Subject: [PATCH 1/2] stdlib/os: fixed typo in container.cue (dest cache folder
 was always "true")

Signed-off-by: Sam Alba <sam.alba@gmail.com>
---
 stdlib/os/container.cue | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/stdlib/os/container.cue b/stdlib/os/container.cue
index 035de1c3..2f06aff0 100644
--- a/stdlib/os/container.cue
+++ b/stdlib/os/container.cue
@@ -113,10 +113,10 @@ import (
 						"\(dest)": o
 						// FIXME: support source path
 					}
-					for dest in cache {
+					for dest, _ in cache {
 						"\(dest)": "cache"
 					}
-					for dest in tmpfs {
+					for dest, _ in tmpfs {
 						"\(dest)": "tmpfs"
 					}
 				}

From 09617b89da523827225758e416377b62f38e54c8 Mon Sep 17 00:00:00 2001
From: Sam Alba <sam.alba@gmail.com>
Date: Wed, 9 Jun 2021 15:22:06 +0200
Subject: [PATCH 2/2] core: replaced persistent cache mounts with directory

Signed-off-by: Sam Alba <sam.alba@gmail.com>
---
 environment/pipeline.go | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/environment/pipeline.go b/environment/pipeline.go
index 08c4f74b..db6e9012 100644
--- a/environment/pipeline.go
+++ b/environment/pipeline.go
@@ -456,11 +456,16 @@ func (p *Pipeline) mount(ctx context.Context, dest string, mnt *compiler.Value)
 		case "cache":
 			return llb.AddMount(
 				dest,
-				llb.Scratch(),
-				llb.AsPersistentCacheDir(
-					p.canonicalPath(mnt),
-					llb.CacheMountShared,
+				llb.Scratch().File(
+					llb.Mkdir("/cache", fs.FileMode(0755)),
+					llb.WithCustomName(p.vertexNamef("Mkdir /cache (cache mount %s)", dest)),
 				),
+				// FIXME: disabled persistent cache mount (gh issue #495)
+				// llb.Scratch(),
+				// llb.AsPersistentCacheDir(
+				// 	p.canonicalPath(mnt),
+				// 	llb.CacheMountShared,
+				// ),
 			), nil
 		case "tmpfs":
 			return llb.AddMount(