[PATCH] Register --sysroot in the driver switches table

[Olivier Hainque via Gcc-patches]

Hello,

This change adjusts the processing of --sysroot to save the option in the
internal "switches" array, which lets self-specs test for it and provide a
default value possibly dependent on environment variables, as in

  --with-specs=%{!-sysroot*:--sysroot=%:getenv("WIND_BASE" /target)}

This helps the use we have of self specs for VxWorks, and
was bootstrapped and regression tested on native 64bit linux.

Ok to commit ?

Thanks in advance,

With Kind Regards,

Olivier


>From 964829ee06ffe1bedcbab6a3b4c92c5d161aaaed Mon Sep 17 00:00:00 2001
From: Olivier Hainque <hain...@adacore.com>
Date: Mon, 20 Dec 2021 17:47:24 +0000
Subject: [PATCH] Register --sysroot in the driver switches table

This change adjusts the processing of --sysroot to save the option in the
internal "switches" array, which lets self-specs test for it and provide a
default value possibly dependent on environment variables, as in

  --with-specs=%{!-sysroot*:--sysroot=%:getenv("WIND_BASE" /target)}

2021-12-20  Olivier Hainque  <hain...@adacore.com>

gcc/
	* gcc.c (driver_handle_option): do_save --sysroot.
---
 gcc/gcc.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/gcc/gcc.c b/gcc/gcc.c
index b75b50b87b2..beb37fe980e 100644
--- a/gcc/gcc.c
+++ b/gcc/gcc.c
@@ -4488,7 +4488,9 @@ driver_handle_option (struct gcc_options *opts,
     case OPT__sysroot_:
       target_system_root = arg;
       target_system_root_changed = 1;
-      do_save = false;
+      /* Saving this option is useful to let self-specs decide to
+         provide a default one.  */
+      do_save = true;
       break;
 
     case OPT_time_:
-- 
2.25.1