This is the mail archive of the cygwin mailing list for the Cygwin project.

Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

RE: jmp_buf size?

What is up with the size of jmp_buf?
It appears that setjmp.h confuses bytes and ints, specifically in the Cygwin case.
_JBLEN should be 13, not 13*4.
or #define _JBTYPE to char, but that doesn't work as easily.

I applied a local hack workaround, something like:
  typedef unsigned char JBTYPE __attribute(align(4));  
  #define _JBTYPE _JBTYPE 
Though my larger goal, of implementing (deprecated-in-favor-of-pthreads) Posix get/make/set/swapcontext I gave up on anyway, at least via layering over setjmp/longjmp. They may be implementable via Win32 fibers, though the overall thing still perhaps dodgy and useless ("user more threads"...).
I realize that jmp_buf is something "deep" and system specific, not to be messed with lightly, but I'm also pretty darn certain that Cygwin declares its own jmp_buf incorrectly.
I also realize that larger than needed is safe, "just" wasteful, and possibly "future proof".
It still seems like a mistake.

 - Jay

Unsubscribe info:
Problem reports:

Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]