Looks good.
/Erik
On 2020-05-08 04:12, Magnus Ihse Bursie wrote:
When building HotSpot with gcc9.x for aarch64, there are a couple of
places that trigger a "warning" (technically a "note") about an ABI
change from earlier versions. The message is
<location>: note: parameter passing for argument of type '<type>
changed in GCC 9.1
This is mentioned prominently in the gcc 9 release notes:
"On Arm targets (arm*-*-*), a bug in the implementation of the
procedure call standard (AAPCS) in the GCC 6, 7 and 8 releases has
been fixed: a structure containing a bit-field based on a 64-bit
integral type and where no other element in a structure required
64-bit alignment could be passed incorrectly to functions. This is an
ABI change. If the option -Wpsabi is enabled (on by default) the
compiler will emit a diagnostic note for code that might be affected."
As the only HotSpot types being warned about are internal and do not
cross library boundaries, and we compile the entire jdk with the same
compiler, these "warnings" are not interesting and just clutter build
logs and cause unnecessary worry.
To suppress these notes, -Wno-psabi should be added to the compiler
options for HotSpot when building for any flavor of ARM, i.e. when the
$VAR_CPU build variable is "arm" or "aarch64". That option is already
present for "arm" because of a similar issue with gcc 4.4. We should
add it for "aarch64".
Bug: https://bugs.openjdk.java.net/browse/JDK-8244653
WebRev:
http://cr.openjdk.java.net/~ihse/JDK-8244653-no-psabi-for-aarch64/webrev.01
/Magnus