-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 11/07/11 03:07, Jakub Jelinek wrote: > On Mon, Nov 07, 2011 at 02:55:02AM -0700, Jeff Law wrote: >> [ Working virtually from Hawaii tonight... :-) ] > > ;) > >> You might legitimately wonder how often this triggers. A GCC >> 4.6.0 checking-enabled compiler sees a .64% codesize improvement >> from this optimization. That's an awful lot of unexecutable >> code. The NULL references come from the VEC implementation and a >> variety of other sources. > > I'd say it is a good idea, though I wonder if the gate shouldn't > also use && flag_delete_null_pointer_checks or at least if the > default for this new option shouldn't be based on > flag_delete_null_pointer_checks. -fno-delete-null-pointer-checks is > documented for quite some time as an option which allows NULL > pointer dereferences (and AFAIK AVR uses it) and people who use > that option will most likely want to disable this optimization > too. Yea, I'd been back and forth on this too -- I don't like gating on the null-pointer-check flag, but I agree that folks using - -fno-delete-null-... probably aren't going to want the new optimization either.
I'll put on my thinking cap and see if I can come up with a good name that encompasses both classes of optimization without getting overly broad. jeff -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQEcBAEBAgAGBQJOuCwXAAoJEBRtltQi2kC7I6UH/2PRnCZxPCHvImghz8IN3ThX IANY9jCSqRzzsebWtTwZ9Y0XE6uQhMpEx/98/ZFZ96OC8rrQkoYR+Jf4DOAP82ja SMDpBETK6BZ7Y/bMKgzJA/QfIlxIcRNScGqZg+F+C3WPqJADHAxCmWGqx/c4/Mwz aylaEBVi/7klqxpmxlkSeN6n0whXf8zL/XmTovpro/6B3oiJaVd1diyrJl3s9vL4 BwjvsbA8ZosLPVCcdLY+9OWjhlnwbOxQQ/xzN8g7knPGNVhe4pXaBmzNiPXGKzrN 1qteyLNdVvnOWj/h1w9a3Ew2EJ3eLUXTytM5BjDfA3gF9Jd1umN81Js+Z/sBRXA= =W7V6 -----END PGP SIGNATURE-----
