* exceptions.cc (_cygtls::handle_exceptions): Only call rtl_unwind when

exiting.  Just return, don't set thread context.
* gendef (_setjmp): Store %fs:0 in jmp_buf.
(_sjfault): Ditto.
(_ljfault): Restore %fs:0 from jmp_buf.
(_longjmp): Ditto.

4 files changed, 22 insertions, 20 deletions

diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index 1e5896fb5..94a578851 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,12 @@
+2008-03-01  Corinna Vinschen  <corinna@vinschen.de>
+
+	* exceptions.cc (_cygtls::handle_exceptions): Only call rtl_unwind when
+	exiting.  Just return, don't set thread context.
+	* gendef (_setjmp): Store %fs:0 in jmp_buf.
+	(_sjfault): Ditto.
+	(_ljfault): Restore %fs:0 from jmp_buf.
+	(_longjmp): Ditto.
+
 2008-02-29  Corinna Vinschen  <corinna@vinschen.de>
 
 	* fhandler_disk_file.cc (fhandler_disk_file::fchmod): Call close_fs
diff --git a/winsup/cygwin/cygtls.cc b/winsup/cygwin/cygtls.cc
index 6b7e0cd51..34ba14934 100644
--- a/winsup/cygwin/cygtls.cc
+++ b/winsup/cygwin/cygtls.cc
@@ -247,8 +247,7 @@ _cygtls::handle_threadlist_exception (EXCEPTION_RECORD *e, exception_list *frame
   extern void *threadlist_exception_return;
   cygheap->threadlist[threadlist_ix]->remove (INFINITE);
   threadlist_ix = 0;
-  RtlUnwind (frame, threadlist_exception_return, e, 0);
-  /* Never returns */
+  return 0;
 }
 
 /* Set up the exception handler for the current thread.  The x86 uses segment
diff --git a/winsup/cygwin/exceptions.cc b/winsup/cygwin/exceptions.cc
index 3b4184db0..56f191851 100644
--- a/winsup/cygwin/exceptions.cc
+++ b/winsup/cygwin/exceptions.cc
@@ -599,8 +599,6 @@ _cygtls::handle_exceptions (EXCEPTION_RECORD *e, exception_list *frame, CONTEXT
       return 1;
     }
 
-  rtl_unwind (frame, e);
-
   debug_printf ("In cygwin_except_handler exc %p at %p sp %p", e->ExceptionCode, in->Eip, in->Esp);
   debug_printf ("In cygwin_except_handler sig %d at %p", si.si_signo, in->Eip);
 
@@ -650,6 +648,7 @@ _cygtls::handle_exceptions (EXCEPTION_RECORD *e, exception_list *frame, CONTEXT
 	      goto out;
 	    }
 
+	  rtl_unwind (frame, e);
 	  open_stackdumpfile ();
 	  exception (e, in);
 	  stackdump ((DWORD) ebp, 0, 1);
@@ -680,21 +679,8 @@ _cygtls::handle_exceptions (EXCEPTION_RECORD *e, exception_list *frame, CONTEXT
   sig_send (NULL, si, &me);	// Signal myself
   me.incyg--;
   e->ExceptionFlags = 0;
-  /* The OS adds an exception list frame to the stack.  It expects to be
-     able to remove this entry after the exception handler returned.
-     However, when unwinding to our frame, our frame becomes the uppermost
-     frame on the stack (%fs:0 points to frame).  This way, our frame
-     is removed from the exception stack and just disappears.  So, we can't
-     just return here or things will be screwed up by the helpful function
-     in (presumably) ntdll.dll.
-
-     So, instead, we will do the equivalent of a longjmp here and return
-     to the caller without visiting any of the helpful code installed prior
-     to this function.  This should work ok, since a longjmp() out of here has
-     to work if linux signal semantics are to be maintained. */
 out:
-  SetThreadContext (GetCurrentThread (), in);
-  return 0; /* Never actually returns.  This is just to keep gcc happy. */
+  return 0;
 }
 
 /* Utilities to call a user supplied exception handler.  */
diff --git a/winsup/cygwin/gendef b/winsup/cygwin/gendef
index 0d7df4b09..28d4b3125 100755
--- a/winsup/cygwin/gendef
+++ b/winsup/cygwin/gendef
@@ -332,12 +332,14 @@ _setjmp:
 	movw	%ax,40(%edi)
 	movw	%ss,%ax
 	movw	%ax,42(%edi)
+	movl	%fs:0,%eax
+	movl	%eax,44(%edi)
 	pushl	%ebx
 	call	stabilize_sig_stack
 	movl	$tls::stackptr(%ebx),%eax		# save stack pointer contents
 	decl	$tls::stacklock(%ebx)
 	popl	%ebx
-	movl	%eax,44(%edi)
+	movl	%eax,48(%edi)
 	popl	%edi
 	movl	\$0,%eax
 	leave
@@ -371,6 +373,8 @@ ___sjfault:
 	movw	%ax,40(%edi)
 	movw	%ss,%ax
 	movw	%ax,42(%edi)
+	movl	%fs:0,%eax
+	movl	%eax,44(%edi)
 	popl	%edi
 	movl	\$0,%eax
 	leave
@@ -391,6 +395,8 @@ ___ljfault:
 	movl	24(%edi),%ebp
 	pushfl
 	popl	%ebx
+	movl	44(%edi),%eax
+	movl	%eax,%fs:0
 	movw	42(%edi),%ax
 	movw	%ax,%ss
 	movl	28(%edi),%esp
@@ -415,7 +421,7 @@ _longjmp:
 	movl	%esp,%ebp
 	movl	8(%ebp),%edi				# address of buffer
 	call	stabilize_sig_stack
-	movl	44(%edi),%eax				# get old signal stack
+	movl	48(%edi),%eax				# get old signal stack
 	movl	%eax,$tls::stackptr(%ebx)		# restore
 	decl	$tls::stacklock(%ebx)			# relinquish lock
 	xorl	%eax,%eax
@@ -430,6 +436,8 @@ _longjmp:
 	movl	24(%edi),%ebp
 	pushfl
 	popl	%ebx
+	movl	44(%edi),%eax
+	movl	%eax,%fs:0
 	movw	42(%edi),%ax
 	movw	%ax,%ss
 	movl	28(%edi),%esp