From: Iain Sandoe <iain@sandoe.co.uk>
Date: Thu, 6 Jan 2022 08:37:18 +0000 (+0000)
Subject: c++, driver: Fix -static-libstdc++ for targets without Bstatic/dynamic.
X-Git-Tag: upstream/13.1.0~2374
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=a846817739c1e7b930d593cd51963d6b46b5dfc6;p=platform%2Fupstream%2Fgcc.git

c++, driver: Fix -static-libstdc++ for targets without Bstatic/dynamic.

The current implementation for swapping between the static and shared c++
runtimes relies on the static linker supporting Bstatic/dynamic which is
not available for every target (Darwin's linker does not support this).

Specs substitution (%s) is an alternative solution for this (which is what
Darwin uses for Fortran, D and Objective-C).  However, specs substitution
requires that the '-static-libstdc++' be preserved in the driver's command
line.  The patch here arranges for this to be done when the configuration
determines that linker support for Bstatic/dynamic is missing.

Signed-off-by: Iain Sandoe <iain@sandoe.co.uk>

gcc/cp/ChangeLog:

	* g++spec.cc (lang_specific_driver): Preserve -static-libstdc++ in
	the driver command line for targets without -Bstatic/dynamic support
	in their static linker.
---

diff --git a/gcc/cp/g++spec.cc b/gcc/cp/g++spec.cc
index 3d3b042..f95d796 100644
--- a/gcc/cp/g++spec.cc
+++ b/gcc/cp/g++spec.cc
@@ -234,7 +234,12 @@ lang_specific_driver (struct cl_decoded_option **in_decoded_options,
 
 	case OPT_static_libstdc__:
 	  library = library >= 0 ? 2 : library;
+#ifdef HAVE_LD_STATIC_DYNAMIC
+	  /* Remove -static-libstdc++ from the command only if target supports
+	     LD_STATIC_DYNAMIC.  When not supported, it is left in so that a
+	     back-end target can use outfile substitution.  */
 	  args[i] |= SKIPOPT;
+#endif
 	  break;
 
 	case OPT_stdlib_: