[newlib-cygwin] Cygwin: Make dumper scan more than first 4GB of VM on x86_64

[Jon TURNEY <jturney@sourceware.org>]

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=2a0e84c8dbe0dba5bd5f5ef652f61a1fd1e8d0fb

commit 2a0e84c8dbe0dba5bd5f5ef652f61a1fd1e8d0fb
Author: Jon Turney <jon.turney@dronecode.org.uk>
Date:   Wed Jul 1 14:00:53 2020 +0100

    Cygwin: Make dumper scan more than first 4GB of VM on x86_64
    
    It's unclear that we need an end address here at all, or can just rely
    on VirtualQueryEx() failing when we reach the end of memory regions.

Diff:
---
 winsup/utils/dumper.cc | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/winsup/utils/dumper.cc b/winsup/utils/dumper.cc
index dcf01e800..ccc4bd12f 100644
--- a/winsup/utils/dumper.cc
+++ b/winsup/utils/dumper.cc
@@ -296,7 +296,7 @@ dumper::collect_memory_sections ()
     return 0;
 
   LPBYTE current_page_address;
-  LPBYTE last_base = (LPBYTE) 0xFFFFFFFF;
+  LPBYTE last_base = (LPBYTE) -1;
   SIZE_T last_size = (SIZE_T) 0;
   SIZE_T done;
 
@@ -307,7 +307,7 @@ dumper::collect_memory_sections ()
   if (hProcess == NULL)
     return 0;
 
-  for (current_page_address = 0; current_page_address < (LPBYTE) 0xFFFF0000;)
+  for (current_page_address = 0; current_page_address < (LPBYTE) -1;)
     {
       if (!VirtualQueryEx (hProcess, current_page_address, &mbi, sizeof (mbi)))
 	break;