diff --git a/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/Utils.java b/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/Utils.java
index 578425874f..411092c1c6 100644
--- a/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/Utils.java
+++ b/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/Utils.java
@@ -194,7 +194,7 @@ public static String tildeExpand(String path) {
         }
     }
 
-    private static Charset UTF8;
+    private static volatile Charset UTF8;
 
     public static Charset getUTF8() {
         if (UTF8 == null) {
diff --git a/mx.fastr/findbugs-exclude.xml b/mx.fastr/findbugs-exclude.xml
index 87ea05706a..854a505851 100644
--- a/mx.fastr/findbugs-exclude.xml
+++ b/mx.fastr/findbugs-exclude.xml
@@ -7,6 +7,10 @@
   <Match>
     <Class name="com.oracle.truffle.r.parser.RLexer"/>
   </Match>
+  <!-- exclude RAccuracyInfo (translated from GnuR) -->
+  <Match>
+    <Class name="com.oracle.truffle.r.runtime.RAccuracyInfo"/>
+  </Match>
   <!-- exclude generated node factory classes -->
   <Match>
       <Class name="~com\.oracle\.truffle\.r\.nodes\..*Factory(\$.*)?"/>