diff -r b58109b7b321 -r 5f260bb27b35 docs/B - Known issues.txt
--- a/docs/B - Known issues.txt	Sat Aug 14 16:37:11 2010 +0200
+++ b/docs/B - Known issues.txt	Thu Apr 07 19:02:56 2011 +0200
@@ -146,3 +146,20 @@
   labelled "Use sjlj for exceptions".
 
 --------------------------------
+Symptoms:
+  Installing the C library headers and start files fails because of
+  missing unwind support, with a message like:
+    configure: error: forced unwind support is required
+
+Explanations:
+  The issue seems to be related to building NPTL on old versions
+  of glibc (and possibly eglibc as well) on some architectures
+  (seen on powerpc, s390, s390x and x86_64).
+
+Fix:
+  None so far. It would require some glibc hacking.
+
+Workaround:
+  Try setting "Force unwind support" in the "C-library" menu.
+
+--------------------------------