On Mon, 14 Jan 2013 14:32:02 -0800 Kent Overstreet <koverstreet@xxxxxxxxxx> wrote: > Bcache: a block layer SSD cache sparc64 gcc-3.4.5: drivers/md/bcache/btree.c: In function `bch_btree_read': drivers/md/bcache/btree.c:266: error: invalid operands to binary + drivers/md/bcache/btree.c: In function `__btree_write': drivers/md/bcache/btree.c:379: error: invalid operands to binary + drivers/md/bcache/btree.c: In function `btree_node_free': drivers/md/bcache/btree.c:980: error: invalid operands to binary + drivers/md/bcache/btree.c: In function `btree_insert_key': drivers/md/bcache/btree.c:1857: error: invalid operands to binary + drivers/md/bcache/btree.c:1857: error: invalid operands to binary + drivers/md/bcache/btree.c:1859: error: invalid operands to binary + drivers/md/bcache/btree.c:1859: error: invalid operands to binary + drivers/md/bcache/btree.c:1864: error: invalid operands to binary + drivers/md/bcache/btree.c:1864: error: invalid operands to binary + drivers/md/bcache/btree.c: In function `btree_split': drivers/md/bcache/btree.c:1934: error: invalid operands to binary + drivers/md/bcache/btree.c: In function `bch_btree_set_root': drivers/md/bcache/btree.c:2159: error: invalid operands to binary + drivers/md/bcache/btree.c: In function `bch_btree_search_recurse': drivers/md/bcache/btree.c:2262: error: invalid operands to binary + drivers/md/bcache/btree.c: In function `bch_btree_refill_keybuf': drivers/md/bcache/btree.c:2330: error: invalid operands to binary + due to #define pbtree(b) (&bch_pbtree(b).s[0]) I don't know why this is happening (presumably a gcc glitch), but returning an 80-byte struct by value from bch_pkey() and bch_pbtree() is just gruesome. The compiler has to allocate the space on the caller stack, pass a hidden pointer into the callee and the callee copies its return value into that caller stack slot. It's slow and consumes stack. Something different, please. -- To unsubscribe from this list: send the line "unsubscribe linux-bcache" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
