From 307c8ff3ef666b7bd5ac733863f2fbb27a9d521e Mon Sep 17 00:00:00 2001
From: Khem Raj <raj.khem@gmail.com>
Date: Fri, 29 Mar 2013 09:12:56 +0400
Subject: [PATCH 20/35] optional libstdc

gcc-runtime builds libstdc++ separately from gcc-cross-*. Its configure tests using g++
will not run correctly since by default the linker will try to link against libstdc++
which shouldn't exist yet. We need an option to disable -lstdc++
option whilst leaving -lc, -lgcc and other automatic library dependencies added by gcc
driver. This patch adds such an option which only disables the -lstdc++.

A "standard" gcc build uses xgcc and hence avoids this. We should ask upstream how to
do this officially, the likely answer is don't build libstdc++ separately.

RP 29/6/10

Signed-off-by: Khem Raj <raj.khem@gmail.com>

Upstream-Status: Inappropriate [embedded specific]
---
 gcc/c-family/c.opt  |    4 ++++
 gcc/cp/g++spec.c    |    1 +
 gcc/doc/invoke.texi |    9 +++++++--
 gcc/gcc.c           |    1 +
 4 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/gcc/c-family/c.opt b/gcc/c-family/c.opt
index 10ae84d..dc3ffdf 100644
--- a/gcc/c-family/c.opt
+++ b/gcc/c-family/c.opt
@@ -1299,6 +1299,10 @@ nostdinc++
 C++ ObjC++
 Do not search standard system include directories for C++
 
+nostdlib++
+Driver
+Do not link standard C++ runtime library
+
 o
 C ObjC C++ ObjC++ Joined Separate
 ; Documented in common.opt
diff --git a/gcc/cp/g++spec.c b/gcc/cp/g++spec.c
index b896eea..f55216b 100644
--- a/gcc/cp/g++spec.c
+++ b/gcc/cp/g++spec.c
@@ -126,6 +126,7 @@ lang_specific_driver (struct cl_decoded_option **in_decoded_options,
       switch (decoded_options[i].opt_index)
 	{
 	case OPT_nostdlib:
+	case OPT_nostdlib__:
 	case OPT_nodefaultlibs:
 	  library = -1;
 	  break;
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index a022622..f15c991 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -190,7 +190,7 @@ in the following sections.
 -frepo  -fno-rtti  -fstats  -ftemplate-backtrace-limit=@var{n} @gol
 -ftemplate-depth=@var{n} @gol
 -fno-threadsafe-statics -fuse-cxa-atexit  -fno-weak  -nostdinc++ @gol
--fno-default-inline  -fvisibility-inlines-hidden @gol
+-nostdlib++ -fno-default-inline  -fvisibility-inlines-hidden @gol
 -fvisibility-ms-compat @gol
 -fext-numeric-literals @gol
 -Wabi  -Wconversion-null  -Wctor-dtor-privacy @gol
@@ -453,7 +453,7 @@ Objective-C and Objective-C++ Dialects}.
 -nostartfiles  -nodefaultlibs  -nostdlib -pie -rdynamic @gol
 -s  -static -static-libgcc -static-libstdc++ @gol
 -static-libasan -static-libtsan @gol
--shared -shared-libgcc  -symbolic @gol
+-shared -shared-libgcc  -symbolic -nostdlib++ @gol
 -T @var{script}  -Wl,@var{option}  -Xlinker @var{option} @gol
 -u @var{symbol}}
 
@@ -9886,6 +9886,11 @@ These entries are usually resolved by entries in
 libc.  These entry points should be supplied through some other
 mechanism when this option is specified.
 
+@item -nostdlib++
+@opindex nostdlib++
+Do not use the standard system C++ runtime libraries when linking.
+Only the libraries you specify will be passed to the linker.
+
 @cindex @option{-lgcc}, use with @option{-nostdlib}
 @cindex @option{-nostdlib} and unresolved references
 @cindex unresolved references and @option{-nostdlib}
diff --git a/gcc/gcc.c b/gcc/gcc.c
index efdb625..477752f 100644
--- a/gcc/gcc.c
+++ b/gcc/gcc.c
@@ -748,6 +748,7 @@ proper position among the other output files.  */
     %(mflib) " STACK_SPLIT_SPEC "\
     %{fprofile-arcs|fprofile-generate*|coverage:-lgcov} " SANITIZER_SPEC " \
     %{!nostdlib:%{!nodefaultlibs:%(link_ssp) %(link_gcc_c_sequence)}}\
+    %{!nostdlib++:}\
     %{!nostdlib:%{!nostartfiles:%E}} %{T*} }}}}}}"
 #endif
 
-- 
1.7.10.4