* dcrt0.cc (child_info_fork::alloc_stack_hard_way): Fix datatype of

	stacksize to SIZE_T.  Cast to SIZE_T in pointer arithmetic.  Slightly
	enhance output in case of a fatal error.
	* fork.cc (frok::parent): Always set ch.stackaddr to DeallocationStack
	value of current thread to help stack reservation in
	child_info_fork::alloc_stack_hard_way along.  Simplify subsequent code
	storing stack values in ch.  Print guardsize in hex, too.

1 files changed, 10 insertions, 7 deletions

diff --git a/winsup/cygwin/dcrt0.cc b/winsup/cygwin/dcrt0.cc
index 0208a9412..d435129d7 100644
--- a/winsup/cygwin/dcrt0.cc
+++ b/winsup/cygwin/dcrt0.cc
@@ -405,7 +405,7 @@ void
 child_info_fork::alloc_stack_hard_way (volatile char *b)
 {
   void *stack_ptr;
-  DWORD stacksize;
+  SIZE_T stacksize;
 
   /* First check if the requested stack area is part of the user heap
      or part of a mmapped region.  If so, we have been started from a
@@ -415,16 +415,19 @@ child_info_fork::alloc_stack_hard_way (volatile char *b)
       && stackbottom <= cygheap->user_heap.max)
       || is_mmapped_region ((caddr_t) stacktop, (caddr_t) stackbottom))
     return;
-
   /* First, try to reserve the entire stack. */
-  stacksize = (char *) stackbottom - (char *) stackaddr;
+  stacksize = (SIZE_T) stackbottom - (SIZE_T) stackaddr;
   if (!VirtualAlloc (stackaddr, stacksize, MEM_RESERVE, PAGE_NOACCESS))
-    api_fatal ("fork: can't reserve memory for stack %p - %p, %E",
-	       stackaddr, stackbottom);
-  stacksize = (char *) stackbottom - (char *) stacktop;
+    {
+      PTEB teb = NtCurrentTeb ();
+      api_fatal ("fork: can't reserve memory for parent stack "
+		 "%p - %p, (child has %p - %p), %E",
+		 stackaddr, stackbottom, teb->DeallocationStack, _tlsbase);
+    }
+  stacksize = (SIZE_T) stackbottom - (SIZE_T) stacktop;
   stack_ptr = VirtualAlloc (stacktop, stacksize, MEM_COMMIT, PAGE_READWRITE);
   if (!stack_ptr)
-    abort ("can't commit memory for stack %p(%d), %E", stacktop, stacksize);
+    abort ("can't commit memory for stack %p(%ly), %E", stacktop, stacksize);
   if (guardsize != (size_t) -1)
     {
       /* Allocate PAGE_GUARD page if it still fits. */