update notice on broken gcc versions in INSTALL file
diff --git a/INSTALL b/INSTALL
index 2994630..5713cd4 100644
--- a/INSTALL
+++ b/INSTALL
@@ -35,8 +35,10 @@
also believed to work, but have not been tested as heavily; prior to
Fall 2012, both had known bugs that affected musl. Firm/cparser is
also believed to work but lacks support for producing shared
-libraries. GCC 4.9.0 is known to have a serious bug (#61144) which
-affects musl and is not supported.
+libraries. GCC 4.9.0 and 4.9.1 are known to have a serious bug
+(#61144) which affects musl. Beginning with version 1.1.4 musl
+attempts to work around the bug, but these compiler versions are still
+considered unstable and unsupported.
