Bug#758115: Disabled wait state X'32EE' on IPL of zIPL

[Stephen Powell <zlinuxman@wowway.com>]

I realize that you've moved on to version 1.25.0-1 (and beyond),
but for what it's worth, I thought you might like to know that I
added -fno-delete-null-pointer-checks to CFLAGS in
zipl/boot/Makefile and recompiled the package (1.24.1-1) with gcc 4.9 and
it now works fine.  The only problem with adding this option to the
Makefile is that the compiler will choke on it if the compiler version
is too old to recognize the option.

And I agree with Bastian.  -fno-delete-null-pointer-checks should be
assumed by default in gcc if -ffreestanding is in effect, unless
-fdelete-null-pointer-checks is explicitly specified.

Null pointer dereferences are perfectly valid when referring to
data in real page 0.  I don't know about other machine architectures,
but on s390/s390x, such references are sometimes necessary.  The case
in point was a valid null pointer dereference to examine the external
interruption code.

I do worry, though, about this being a more general problem.  What about
the interrupt handler in the Linux kernel?  Or any other portion of the
kernel that needs to examine (or change) data in real page 0 for
whatever reason?

-- 
  .''`.     Stephen Powell    
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