Merge branch 'release-0.55.6'

3 files changed, 22 insertions, 0 deletions

diff --git a/docs/content/en/news/0.55.6-relnotes/index.md b/docs/content/en/news/0.55.6-relnotes/index.md
new file mode 100644
index 000000000..4be66d556
--- /dev/null
+++ b/docs/content/en/news/0.55.6-relnotes/index.md
@@ -0,0 +1,13 @@
+
+---
+date: 2019-05-18
+title: "0.55.6"
+description: "0.55.6"
+categories: ["Releases"]
+images:
+- images/blog/hugo-bug-poster.png
+
+---
+
+	This is a bug-fix release with one important fix. There have been reports about infrequent paginator crashes when running the Hugo server since 0.55.0. The reason have been narrowed down to that of parallel rebuilds. This isn't a new thing, but the changes in 0.55.0 made it extra important to serialize the page initialization. This release fixes that by protecting the `Build` method with a lock when running in server mode. [95ce2a40](https://github.com/gohugoio/hugo/commit/95ce2a40e734bb82b69f9a64270faf3ed69c92cc) [@bep](https://github.com/bep) [#5885](https://github.com/gohugoio/hugo/issues/5885)[#5968](https://github.com/gohugoio/hugo/issues/5968)
+
diff --git a/hugolib/hugo_sites.go b/hugolib/hugo_sites.go
index fdd4e890c..e852e7f1d 100644
--- a/hugolib/hugo_sites.go
+++ b/hugolib/hugo_sites.go
@@ -62,6 +62,9 @@ type HugoSites struct {
 	// If this is running in the dev server.
 	running bool
 
+	// Serializes rebuilds when server is running.
+	runningMu sync.Mutex
+
 	// Render output formats for all sites.
 	renderFormats output.Formats
 
diff --git a/hugolib/hugo_sites_build.go b/hugolib/hugo_sites_build.go
index d748a0169..7f725def2 100644
--- a/hugolib/hugo_sites_build.go
+++ b/hugolib/hugo_sites_build.go
@@ -31,6 +31,12 @@ import (
 // Build builds all sites. If filesystem events are provided,
 // this is considered to be a potential partial rebuild.
 func (h *HugoSites) Build(config BuildCfg, events ...fsnotify.Event) error {
+	if h.running {
+		// Make sure we don't trigger rebuilds in parallel.
+		h.runningMu.Lock()
+		defer h.runningMu.Unlock()
+	}
+
 	ctx, task := trace.NewTask(context.Background(), "Build")
 	defer task.End()