INSTALL

@@ -52,9 +52,8 @@ You will also probably need GNU m4 (perhaps installed as gm4).
 Requirements
 ------------
 
-First of all, you will need a C++11 standard conforming compiler, like
-g++ (at least 5.0, to have proper std::regex & std::string) or
-clang++.
+First of all, you will need a C++11 standard conforming compiler, like g++ (at
+least 5.0, to have proper std::regex & std::string) or clang++.
 
 LyX makes great use of the C++ Standard Library. This means that gcc
 users will have to install the relevant libstdc++ library to be able

config/lyxinclude.m4

@@ -210,6 +210,32 @@ AC_DEFUN([LYX_CXX_CXX11_FLAGS],
 ])
 
 
+dnl Usage: LYX_CXX_USE_CALL_ONCE
+dnl check whether we can use std::call_once and set the
+dnl LYX_USE_STD_CALL_ONCE macro and conditional accordingly.
+AC_DEFUN([LYX_CXX_USE_CALL_ONCE],
+[AC_MSG_CHECKING([for std::call_once availability])
+   save_CPPFLAGS=$CPPFLAGS
+   CPPFLAGS="$AM_CPPFLAGS $CPPFLAGS"
+   save_CXXFLAGS=$CXXFLAGS
+   CXXFLAGS="$AM_CXXFLAGS $CXXFLAGS"
+   AC_LINK_IFELSE([AC_LANG_PROGRAM([[
+	#include <mutex>
+	static std::once_flag flag;
+     ]], [[
+	std::call_once(flag, [](){ return; });
+   ]])],[lyx_std_call_once=yes],[lyx_std_call_once=no])
+   CXXFLAGS=$save_CXXFLAGS
+   CPPFLAGS=$save_CPPFLAGS
+   AC_MSG_RESULT([$lyx_std_call_once])
+
+ if test $lyx_std_call_once = yes ; then
+  AC_DEFINE([LYX_USE_STD_CALL_ONCE], 1, [define to 1 if std::call_once is supported by the compiler])
+ fi
+ AM_CONDITIONAL([LYX_USE_STD_CALL_ONCE], test $lyx_std_call_once = yes)
+])
+
+
 dnl Usage: LYX_LIB_STDCXX: set lyx_cv_lib_stdcxx to yes if the STL library is libstdc++.
 AC_DEFUN([LYX_LIB_STDCXX],
 [AC_CACHE_CHECK([whether STL is libstdc++],
@@ -222,6 +248,19 @@ AC_DEFUN([LYX_LIB_STDCXX],
 ])
 
 
+dnl Usage: LYX_LIB_STDCXX_CXX11_ABI: set lyx_cv_lib_stdcxx_cxx11_abi to yes
+dnl        if the STL library is GNU libstdc++ and the C++11 ABI is used.
+AC_DEFUN([LYX_LIB_STDCXX_CXX11_ABI],
+[AC_CACHE_CHECK([whether STL is libstdc++ using the C++11 ABI],
+               [lyx_cv_lib_stdcxx_cxx11_abi],
+[AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include<vector>]], [[
+#if ! defined(_GLIBCXX_USE_CXX11_ABI) || ! _GLIBCXX_USE_CXX11_ABI
+	    this is not libstdc++ using the C++11 ABI
+#endif
+]])],[lyx_cv_lib_stdcxx_cxx11_abi=yes],[lyx_cv_lib_stdcxx_cxx11_abi=no])])
+])
+
+
 AC_DEFUN([LYX_PROG_CXX],
 [AC_REQUIRE([AC_PROG_CXX])
 AC_REQUIRE([AC_PROG_CXXCPP])
@@ -236,8 +275,22 @@ AC_LANG_PUSH(C++)
 LYX_PROG_CLANG
 LYX_CXX_CXX11_FLAGS($enable_cxx_mode)
 LYX_LIB_STDCXX
+LYX_LIB_STDCXX_CXX11_ABI
+LYX_CXX_USE_CALL_ONCE
 AC_LANG_POP(C++)
 
+if test $lyx_cv_lib_stdcxx = "yes" ; then
+  if test $lyx_cv_lib_stdcxx_cxx11_abi = "yes" ; then
+    AC_DEFINE(USE_GLIBCXX_CXX11_ABI, 1, [use GNU libstdc++ with C++11 ABI])
+  else
+    AC_DEFINE(STD_STRING_USES_COW, 1, [std::string uses copy-on-write])
+  fi
+else
+  if test $lyx_cv_prog_clang = "yes" ; then
+    AC_DEFINE(USE_LLVM_LIBCPP, 1, [use libc++ provided by llvm instead of GNU libstdc++])
+  fi
+fi
+
 ### We might want to get or shut warnings.
 AC_ARG_ENABLE(warnings,
   AS_HELP_STRING([--enable-warnings],[tell the compiler to display more warnings]),,
@@ -310,7 +363,7 @@ if test x$GXX = xyes; then
   fi
 
   case $gxx_version in
-      2.*|3.*|4.*) AC_MSG_ERROR([gcc >= 5 is required]);;
+      2.*|3.*|4.@<:@0-8@:>@*) AC_MSG_ERROR([gcc >= 4.9 is required]);;
   esac
 
   AM_CXXFLAGS="$lyx_optim $AM_CXXFLAGS"

src/BranchList.cpp

@@ -114,14 +114,12 @@ void Branch::setColors(string const & lmcol, string const & dmcol)
 	string lmcolor = lmcolor_;
 	string dmcolor = dmcolor_;
 	if (lmcolor == "none")
-		lmcolor = "background";
-	// if we have background color, keep semantic value, as system colors might vary
-	else if (lmcolor != "background" && (lmcolor.size() != 7 || lmcolor[0] != '#'))
+		lmcolor = lcolor.getX11HexName(Color_background);
+	else if (lmcolor.size() != 7 || lmcolor[0] != '#')
 		lmcolor = lcolor.getX11HexName(lcolor.getFromLyXName(lmcolor));
 	if (dmcolor == "none")
-		dmcolor = "background";
-	// if we have background color, keep semantic value, as system colors might vary
-	else if (dmcolor != "background" && (dmcolor.size() != 7 || dmcolor[0] != '#'))
+		dmcolor = lcolor.getX11HexName(Color_background, true);
+	else if (dmcolor.size() != 7 || dmcolor[0] != '#')
 		dmcolor = lcolor.getX11HexName(lcolor.getFromLyXName(dmcolor), true);
 
 	// FIXME UNICODE

src/BufferView.cpp

@@ -1676,7 +1676,7 @@ void BufferView::dispatch(FuncRequest const & cmd, DispatchResult & dr)
 					success = setCursorFromEntries({id, pos},
 					                               {id_end, pos_end});
 				}
-				if (success && scrollToCursor(d->cursor_, SCROLL_TOP))
+				if (success && scrollToCursor(d->cursor_, SCROLL_TOGGLE))
 						dr.screenUpdate(Update::Force);
 			} else {
 				// Switch to other buffer view and resend cmd

src/insets/InsetBranch.cpp

@@ -154,10 +154,6 @@ ColorCode InsetBranch::backgroundColor(PainterInfo const & pi) const
 	// FIXME UNICODE
 	string const branchcol = "branch" + branch_id + to_utf8(params_.branch);
 	ColorCode c = lcolor.getFromLyXName(branchcol);
-	// if we have background color, set to semantic value, as system colors
-	// might vary
-	if (lcolor.getX11HexName(c, (theApp() && theApp()->isInDarkMode())) == "background")
-		c = Color_background;
 	if (c == Color_none)
 		c = Color_error;
 	return c;

src/support/debug.h

@@ -17,6 +17,20 @@
 
 #include "support/docstring.h"
 
+// Forward definitions do not work with libc++
+// but ios_base has already been defined in strfwd
+// if compiling with it
+#ifndef USE_LLVM_LIBCPP
+namespace std {
+
+class ios_base;
+
+template<typename CharT, typename Traits> class basic_streambuf;
+typedef basic_streambuf<char, char_traits<char> > streambuf;
+
+} // namespace std
+#endif
+
 
 // Make sure at compile time that sizeof(unsigned long long) >= 8
 typedef char p__LINE__[ (sizeof(unsigned long long) > 7) ? 1 : -1];