Re: Make ip.h and tcp.h work under -fnative-struct or -mms-bitfields
Sorry for my ignorance and noise, but I still want to ask what problems could occur if I use u_char instead of u_int to denote bit fields. Any answer is appreciated. (Of course I would like to have a header file working across all my Windows compilers. Others may appreciate it too.) Best regards, Wu Yongwei --- Original Message from Christopher Faylor --- Danny's suggestion is correct. The rest of the header files which accomodate this are probably using __attribute__((packed)) . The argument that the header works ok for you on MSVC is a non-issue for cygwin. cgf
Re: Make ip.h and tcp.h work under -fnative-struct or -fms-bitfields
On Mon, Nov 11, 2002 at 04:55:25PM +0800, Wu Yongwei wrote: >Hi, > >What's the status of this patch? > >-- >ChangeLog: > >2002-10-28 Wu Yongwei <[EMAIL PROTECTED]> > >* ip.h (struct ip): Use u_char to indicate bitfields to make it >work with -fnative-struct/-fms-bitfields. >(struct ip_timestamp): Ditto. >* tcp.h (struct tcphdr): Ditto. >-- > >Am I really going the wrong way (any examples)? Or should I submit a new >patch as Danny suggests? Danny's suggestion is correct. The rest of the header files which accomodate this are probably using __attribute__((packed)) . The argument that the header works ok for you on MSVC is a non-issue for cygwin. cgf
dll_index NO_COPY patch
The attached patch fixes the problem described in the following thread:
http://cygwin.com/ml/cygwin-developers/2002-11/msg00019.html
Given the following facts:
1. During fork(), fork_copy() is run after
dll_list::load_after_fork().
2. The static dll_index variable in include/cygwin/cygwin_dll.h is
not marked NO_COPY.
3. The dll structure allocated by dll_list::alloc() is not
guaranteed to be the same in the parent and child.
I believe that the following is the correct root cause analysis of the
problem:
When #3 above occurs, fork_copy() overwrites the child's dll_index
with the parent's value. This causes dll_list::detach() to access
unallocated memory which in turn causes the child to stackdump.
Jason
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Index: include/cygwin/cygwin_dll.h
===
RCS file: /cvs/src/src/winsup/cygwin/include/cygwin/cygwin_dll.h,v
retrieving revision 1.8
diff -u -p -r1.8 cygwin_dll.h
--- include/cygwin/cygwin_dll.h 11 Sep 2001 20:01:01 - 1.8
+++ include/cygwin/cygwin_dll.h 11 Nov 2002 15:23:39 -
@@ -12,6 +12,7 @@ details. */
#define __CYGWIN_CYGWIN_DLL_H__
#include
+#include "winsup.h"
#ifdef __cplusplus
#define CDECL_BEGIN extern "C" {
@@ -39,7 +40,7 @@ static int __dllMain (int a, char **b, c
return Entry (storedHandle, storedReason, storedPtr); \
}\
\
-static DWORD dll_index; \
+static NO_COPY DWORD dll_index; \
\
int WINAPI _cygwin_dll_entry (HINSTANCE h, DWORD reason, void *ptr) \
{\
Mon Nov 11 10:45:37 2002 <[EMAIL PROTECTED]>
* include/cygwin/cygwin_dll.h: Add #include "winsup.h".
(dll_index): Make NO_COPY.
Re: Make ip.h and tcp.h work under -fnative-struct or -fms-bitfields
Wu Yongwei <[EMAIL PROTECTED]> wrote: > work with -fnative-struct/-fms-bitfields. It's -mms-bitfields. Max.
Re: Make ip.h and tcp.h work under -fnative-struct or -fms-bitfields
Hi, What's the status of this patch? -- ChangeLog: 2002-10-28 Wu Yongwei <[EMAIL PROTECTED]> * ip.h (struct ip): Use u_char to indicate bitfields to make it work with -fnative-struct/-fms-bitfields. (struct ip_timestamp): Ditto. * tcp.h (struct tcphdr): Ditto. -- Am I really going the wrong way (any examples)? Or should I submit a new patch as Danny suggests? Best regards, Wu Yongwei
