[review v2] hurd: Fix GCC 10 -Warray-bounds warning in init-first.c

["Florian Weimer (Code Review)" <gerrit@gnutoolchain-gerrit.osci.io>]

Change URL: https://gnutoolchain-gerrit.osci.io/r/c/glibc/+/657
......................................................................

hurd: Fix GCC 10 -Warray-bounds warning in init-first.c

The trampoline code should really be rewritten in assembler because
this is all very undefined at the C level.

Change-Id: Ided58244ca0ee48892519faac5ac222a4e02dec4
---
M sysdeps/mach/hurd/i386/init-first.c
1 file changed, 10 insertions(+), 0 deletions(-)



diff --git a/sysdeps/mach/hurd/i386/init-first.c b/sysdeps/mach/hurd/i386/init-first.c
index f1f1c40..286d2a0 100644
--- a/sysdeps/mach/hurd/i386/init-first.c
+++ b/sysdeps/mach/hurd/i386/init-first.c
@@ -30,6 +30,7 @@
 
 #include <ldsodefs.h>
 #include <fpu_control.h>
+#include <libc-diag.h>
 
 extern void __mach_init (void);
 extern void __init_misc (int, char **, char **);
@@ -144,9 +145,16 @@
 static inline void
 init (int *data)
 {
+  /* data is the address of the argc parameter to _dl_init_first or
+     doinit1 in _hurd_stack_setup, so the array subscripts are
+     undefined.  */
+  DIAG_PUSH_NEEDS_COMMENT;
+  DIAG_IGNORE_NEEDS_COMMENT (10, "-Warray-bounds");
+
   int argc = *data;
   char **argv = (void *) (data + 1);
   char **envp = &argv[argc + 1];
+
   struct hurd_startup_data *d;
 
   /* Since the cthreads initialization code uses malloc, and the
@@ -265,6 +273,8 @@
 	 restored by function return.  */
       asm volatile ("# a %0 c %1" : : "a" (usercode), "c" (&init1));
     }
+
+  DIAG_POP_NEEDS_COMMENT;	/* -Warray-bounds.  */
 }
 
 /* These bits of inline assembler used to be located inside `init'.

-- 
Gerrit-Project: glibc
Gerrit-Branch: master
Gerrit-Change-Id: Ided58244ca0ee48892519faac5ac222a4e02dec4
Gerrit-Change-Number: 657
Gerrit-PatchSet: 2
Gerrit-Owner: Florian Weimer <fweimer@redhat.com>
Gerrit-MessageType: newpatchset