Re: [Maria-developers] [patch 04/11] Avoid Valgrind complaint about GCC-generated overlapping memcpy()

Hi!

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"knielsen" == knielsen writes:

knielsen> (Some versions of GCC implement struct_var = struct_var using knielsen> memcpy(), which violates specs for memcpy() (not allowed for knielsen> overlapping source and destination). knielsen> GCC bug 19410: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19410 knielsen> === modified file 'sql/sql_select.cc' knielsen> --- knielsen> sql/sql_select.cc | 13 +++++++++++-- knielsen> 1 file changed, 11 insertions(+), 2 deletions(-) knielsen> Index: sql/sql_select.cc knielsen> =================================================================== knielsen> --- sql/sql_select.cc.orig 2009-04-07 13:40:36.000000000 +0200 knielsen> +++ sql/sql_select.cc 2009-04-07 13:42:10.000000000 +0200 knielsen> @@ -1994,8 +1994,17 @@ JOIN::exec() knielsen> tmp_fields_list2, tmp_all_fields2, knielsen> fields_list.elements, tmp_all_fields1)) knielsen> DBUG_VOID_RETURN; knielsen> - curr_join->tmp_fields_list2= tmp_fields_list2; knielsen> - curr_join->tmp_all_fields2= tmp_all_fields2; knielsen> +#ifdef HAVE_purify knielsen> + /* knielsen> + Some GCCs use memcpy() for struct assignment, even for x=x. knielsen> + GCC bug 19410: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19410 knielsen> + */ knielsen> + if (curr_join != this) knielsen> +#endif knielsen> + { knielsen> + curr_join->tmp_fields_list2= tmp_fields_list2; knielsen> + curr_join->tmp_all_fields2= tmp_all_fields2; knielsen> + } knielsen> } knielsen> curr_fields_list= &curr_join->tmp_fields_list2; knielsen> curr_all_fields= &curr_join->tmp_all_fields2; ok to push. I think this is actually something that should be fixed in valgrind; Copying over itself shouldn't give a warning. (Or at least, one should be able to disable it) Regards, Monty