Hi, Richard,
On May 26, 2021, at 6:18 AM, Richard Biener <rguent...@suse.de<mailto:rguent...@suse.de>> wrote: On Wed, 12 May 2021, Qing Zhao wrote: Hi, This is the 3rd version of the patch for the new security feature for GCC. Please take look and let me know your comments and suggestions. +/* Returns true when the given TYPE has padding inside it. + return false otherwise. */ +bool +type_has_padding (tree type) +{ + switch (TREE_CODE (type)) + { + case RECORD_TYPE: + { btw, there's __builtin_clear_padding and a whole machinery around it in gimple-fold.c, I'm sure that parts could be re-used if they are neccessary in the end. To address the above suggestion: My study shows: the call to __builtin_clear_padding is expanded during gimplification phase. And there is no __bultin_clear_padding expanding during rtx expanding phase. However, for -ftrivial-auto-var-init, padding initialization should be done both in gimplification phase and rtx expanding phase. since the __builtin_clear_padding might not be good for rtx expanding, reusing __builtin_clear_padding might not work. Let me know if you have any more comments on this. Thanks. Qing
