Upgrade tested Go version to 1.18.5.
diff --git a/.github/workflows/measure-size.yml b/.github/workflows/measure-size.yml
index c9c0c0e..7118f3f 100644
--- a/.github/workflows/measure-size.yml
+++ b/.github/workflows/measure-size.yml
@@ -11,7 +11,7 @@
           fetch-depth: 0
       - uses: actions/setup-go@v2
         with:
-          go-version: '~1.18.4'
+          go-version: '~1.18.5'
       - uses: gopherjs/output-size-action/measure@main
         with:
           name: jQuery TodoMVC
diff --git a/circle.yml b/circle.yml
index afc4369..bdbb0b3 100644
--- a/circle.yml
+++ b/circle.yml
@@ -54,7 +54,7 @@
 parameters:
   go_version:
     type: string
-    default: "1.18.4"
+    default: "1.18.5"
   nvm_version:
     type: string
     default: "0.38.0"
diff --git a/compiler/version_check.go b/compiler/version_check.go
index 35e86bf..6dbc9ae 100644
--- a/compiler/version_check.go
+++ b/compiler/version_check.go
@@ -13,7 +13,7 @@
 )
 
 // Version is the GopherJS compiler version string.
-const Version = "1.18.0+go1.18.4"
+const Version = "1.18.0+go1.18.5"
 
 // GoVersion is the current Go 1.x version that GopherJS is compatible with.
 const GoVersion = 18