[gcc r17-4970] Ada: Fix oversight in GNAT.Sockets.Thin

[Eric Botcazou via Gcc-cvs]

https://gcc.gnu.org/g:b4ec88ebf3e3f495736deb25849990034d04195e

commit r17-4970-gb4ec88ebf3e3f495736deb25849990034d04195e
Author: Hodong Kim <hod...@nimfsoft.com>
Date:   Wed Oct 7 23:41:24 2026 +0200

    Ada: Fix oversight in GNAT.Sockets.Thin
    
    As reported in the PR, both C_Accept and C_Socket call Disable_SIGPIPE
    unconditionally, in other words even though the descriptor is invalid.
    
    gcc/ada/
            PR ada/127759
            * libgnat/g-socthi.adb (C_Accept): Do not call Disable_SIGPIPE
            on failure.
            (C_Socket): Likewise.

Diff:
---
 gcc/ada/libgnat/g-socthi.adb | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/gcc/ada/libgnat/g-socthi.adb b/gcc/ada/libgnat/g-socthi.adb
index f7fa4007dd1b..a369c98a9e22 100644
--- a/gcc/ada/libgnat/g-socthi.adb
+++ b/gcc/ada/libgnat/g-socthi.adb
@@ -187,7 +187,10 @@ package body GNAT.Sockets.Thin is
          Discard := C_Ioctl (R, SOSC.FIONBIO, Val'Access);
       end if;
 
-      Disable_SIGPIPE (R);
+      if R /= Failure then
+         Disable_SIGPIPE (R);
+      end if;
+
       return R;
    end C_Accept;
 
@@ -533,7 +536,11 @@ package body GNAT.Sockets.Thin is
          Discard := C_Ioctl (R, SOSC.FIONBIO, Val'Access);
          Set_Non_Blocking_Socket (R, False);
       end if;
-      Disable_SIGPIPE (R);
+
+      if R /= Failure then
+         Disable_SIGPIPE (R);
+      end if;
+
       return R;
    end C_Socket;