<AWT Dev> RfR JDK-8077707 jdk9 b58 cannot run any graphical application with JAWS running

Pete Brunet peter.brunet at oracle.com
Wed Jul 22 23:53:39 UTC 2015

Please review this patch which cures a problem that appears since 9 b58
when the compiler was switched to VS2013 and as a result turned on the
High Entropy Virtual Addresses bit in the executable header when running
on Win 8.1. 

With the high-entropy 64-bit address space layout randomization option
enabled, all memory addresses in a 64-bit app are guaranteed to be above
4gb. This means that if any module has latent pointer truncation issues
in 64-bit builds, these issues will manifest themselves when this flag
is set.

The fix is to change the wparam type from UINT to WPARAM and the lparam
type from LONG to LPARAM.

Using UINT/LONG would cause truncation in the upper 32 bits of


Thanks, Pete

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