[PATCH] S/390: Fix layout of struct sigaction_t

[Stefan Liebler via Gcc-patches]

Hi,

the ordering of some fields in  struct sigaction on s390x (64bit)
differs compared to s390 and other architectures.
This patch adjusts this order according to the definition of
<glibc-src>/sysdeps/unix/sysv/linux/s390/bits/sigaction.h

Without this fix e.g. the call
sigaction( suspendSignalNumber, &sigusr1, null ) in thread.d
leads to setting the sa_restorer field to 0xffffffffffffffff.
In case a signal, the signal handler returns to this address
and the process stops with a SIGILL.

This was observable in several execution testcases on s390x:
libphobos.druntime/core/thread.d
libphobos.druntime_shared/core/thread.d
libphobos.thread/tlsgc_sections.d
libphobos.allocations/tls_gc_integration.d
libphobos.phobos/std/parallelism.d
libphobos.phobos_shared/std/parallelism.d
libphobos.shared/host.c
libphobos.shared/linkD.c
libphobos.shared/linkDR.c
libphobos.shared/link_linkdep.d
libphobos.shared/load.d
libphobos.shared/loadDR.c
libphobos.shared/load_linkdep.d
libphobos.shared/load_loaddep.d

Bye,
Stefan

--

libphobos/ChangeLog:

2020-03-23  Stefan Liebler  <s...@linux.ibm.com>

        * libphobos/libdruntime/core/sys/posix/signal.d:
        Add struct sigaction_t for SystemZ.

commit 0986df3847c287c144b2e38d3ec1d423b934d7a8
Author: Stefan Liebler <s...@linux.ibm.com>
Date:   Tue Mar 17 17:00:44 2020 +0100

    S/390: Fix layout of struct sigaction_t
    
    The ordering of some fields in  struct sigaction on s390x (64bit)
    differs compared to s390 and other architectures.
    This patch adjusts this order according to the definition of
    <glibc-src>/sysdeps/unix/sysv/linux/s390/bits/sigaction.h
    
    Without this fix e.g. the call
    sigaction( suspendSignalNumber, &sigusr1, null ) in thread.d
    leads to setting the sa_restorer field to 0xffffffffffffffff.
    In case a signal, the signal handler returns to this address
    and the process stops with a SIGILL.
    
    This was observable in several execution testcases on s390x:
    libphobos.druntime/core/thread.d
    libphobos.druntime_shared/core/thread.d
    libphobos.thread/tlsgc_sections.d
    libphobos.allocations/tls_gc_integration.d
    libphobos.phobos/std/parallelism.d
    libphobos.phobos_shared/std/parallelism.d
    libphobos.shared/host.c
    libphobos.shared/linkD.c
    libphobos.shared/linkDR.c
    libphobos.shared/link_linkdep.d
    libphobos.shared/load.d
    libphobos.shared/loadDR.c
    libphobos.shared/load_linkdep.d
    libphobos.shared/load_loaddep.d
    
    libphobos/ChangeLog:
    
    2020-03-23  Stefan Liebler  <s...@linux.ibm.com>
    
            * libphobos/libdruntime/core/sys/posix/signal.d:
            Add struct sigaction_t for SystemZ.

diff --git a/libphobos/libdruntime/core/sys/posix/signal.d b/libphobos/libdruntime/core/sys/posix/signal.d
index ed3985eee4d..5abcdac1355 100644
--- a/libphobos/libdruntime/core/sys/posix/signal.d
+++ b/libphobos/libdruntime/core/sys/posix/signal.d
@@ -575,24 +575,51 @@ else
 
 version (CRuntime_Glibc)
 {
-    struct sigaction_t
+    version (SystemZ)
     {
-        static if ( true /* __USE_POSIX199309 */ )
+        struct sigaction_t
         {
-            union
+            static if ( true /* __USE_POSIX199309 */ )
+            {
+                union
+                {
+                    sigfn_t     sa_handler;
+                    sigactfn_t  sa_sigaction;
+                }
+            }
+            else
             {
                 sigfn_t     sa_handler;
-                sigactfn_t  sa_sigaction;
             }
+            int             __glibc_reserved0;
+            int             sa_flags;
+
+            void function() sa_restorer;
+
+            sigset_t        sa_mask;
         }
-        else
+    }
+    else
+    {
+        struct sigaction_t
         {
-            sigfn_t     sa_handler;
-        }
-        sigset_t        sa_mask;
-        int             sa_flags;
+            static if ( true /* __USE_POSIX199309 */ )
+            {
+                union
+                {
+                    sigfn_t     sa_handler;
+                    sigactfn_t  sa_sigaction;
+                }
+            }
+            else
+            {
+                sigfn_t     sa_handler;
+            }
+            sigset_t        sa_mask;
+            int             sa_flags;
 
-        void function() sa_restorer;
+            void function() sa_restorer;
+        }
     }
 }
 else version (CRuntime_Musl)