Fix visibility.

configure.ac

@@ -39,6 +39,8 @@ LT_PREREQ([2.2])
 LT_INIT([disable-static])
 LT_LANG([C++])
 gl_VISIBILITY
+AS_IF([ test -n "$CFLAG_VISIBILITY" ], [ CPPFLAGS="$CPPFLAGS $CFLAG_VISIBILITY" ])
+
 PANDORA_PLATFORM
 m4_ifdef([AM_SILENT_RULES],[AM_SILENT_RULES([yes])])
 AX_ASSERT

libgearman/include.am

@@ -52,6 +52,7 @@ noinst_HEADERS+= \
 noinst_LTLIBRARIES+= libgearman/libgearmancore.la
 libgearman_libgearmancore_la_SOURCES= \
 				      libgearman/allocator.cc \
+				      libgearman/backtrace.cc \
 				      libgearman/byteorder.cc \
 				      libgearman/command.cc \
 				      libgearman/connection.cc \