Fix bugs #6078 and #9364

[lyx.git] / src / support / strfwd.h

diff --git a/src/support/strfwd.h b/src/support/strfwd.h
index ee4888abd44e0dd05557571b1db91226e11fed29..8419b513519b2d2d017247686fbac6169478d428 100644 (file)
--- a/src/support/strfwd.h
+++ b/src/support/strfwd.h
@@ -29,7 +29,10 @@ namespace lyx { typedef boost::uint32_t char_type; }
 #endif
 
 // Forward definitions do not work with libc++
-#ifdef USE_LLVM_LIBCPP
+// For gcc5 with the new std::string ABI forward declarations would work in
+// principle, but I am not sure whether we want non-standard
+// "namespace __cxx11" in our sources.
+#if defined(USE_LLVM_LIBCPP) || defined(USE_GLIBCXX_CXX11_ABI)
 #include <string>
 #else