[PATCH FOR REVIEW] Building ExtensionSubtables.cpp should use -fno-strict-aliasing

[Andrew Hughes]

At present, the building of ExtensionSubtables.cpp produces a warning:

../../../src/share/native/sun/font/layout/ExtensionSubtables.cpp:57:31:
warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing]

due to this code:

// read a 32-bit value that might only be 16-bit-aligned in memory                                                              
#define READ_LONG(code) (le_uint32)((SWAPW(*(le_uint16*)&code) << 16) + SWAPW(*(((le_uint16*)&code) + 1)))

where code is a le_uint32.

This can be avoided by setting -fno-strict-aliasing, as done in this webrev:

http://cr.openjdk.java.net/~andrew/no-strict-aliasing/

making the code safer in the process.

Ok for jdk8?  If so, can I have a bug ID for this please?

Thanks,
-- 
Andrew :)

Free Java Software Engineer
Red Hat, Inc. (http://www.redhat.com)

PGP Key: 248BDC07 (https://keys.indymedia.org/)
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