Re: [U-Boot] [BUG] net: nfs: -Werror=address-of-packed-member
On 9/3/19 11:32 PM, Joe Hershberger wrote: Hi Heinrich, On Mon, Sep 2, 2019 at 4:39 PM Heinrich Schuchardt wrote: Hello Joe, GCC 9.2.1 (of Debian Bullseye) produces the warnings below when building pine64-lts_defconfig. Is it really necessary to define struct rpc_t as packed? The structure is composed out of uint32_t only. So shouldn't it be naturally packed without the attribute? I guess this won't cause problems on 64-bit with the union sharing memory, right? The addresses of all members of a union is the same. See C99 standard 6.2.7.1, paragraph 14. The alignment requirement on an array is not stricter than on its elements. Anyway the arrays in the union start at a multiple of 64bit after the start of the structure. Both on x86_64 and on arm64 is 24 bytes after without 'packed' - just where you would expect it. Best regards Heinrich net/nfs.c: In function ‘rpc_req’: net/nfs.c:199:18: error: taking address of packed member of ‘struct rpc_t’ may result in an unaligned pointer value [-Werror=address-of-packed-member] 199 | p = (uint32_t *)&(rpc_pkt.u.call.data); | ^~ net/nfs.c: In function ‘nfs_readlink_reply’: net/nfs.c:631:46: error: taking address of packed member of ‘struct rpc_t’ may result in an unaligned pointer value [-Werror=address-of-packed-member] 631 |nfs3_get_attributes_offset(rpc_pkt.u.reply.data); | ~~~^ LD drivers/block/built-in.o net/nfs.c: In function ‘nfs_read_reply’: net/nfs.c:692:46: error: taking address of packed member of ‘struct rpc_t’ may result in an unaligned pointer value [-Werror=address-of-packed-member] 692 |nfs3_get_attributes_offset(rpc_pkt.u.reply.data); | ~~~^ Best regards Heinrich ___ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot ___ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot
Re: [U-Boot] [BUG] net: nfs: -Werror=address-of-packed-member
Hi Heinrich, On Mon, Sep 2, 2019 at 4:39 PM Heinrich Schuchardt wrote: > > Hello Joe, > > GCC 9.2.1 (of Debian Bullseye) produces the warnings below when building > pine64-lts_defconfig. Is it really necessary to define struct rpc_t as > packed? The structure is composed out of uint32_t only. So shouldn't it > be naturally packed without the attribute? I guess this won't cuase problems on 64-bit with the union sharing memory, right? > > net/nfs.c: In function ‘rpc_req’: > net/nfs.c:199:18: error: taking address of packed member of ‘struct > rpc_t’ may result in an unaligned pointer value > [-Werror=address-of-packed-member] >199 | p = (uint32_t *)&(rpc_pkt.u.call.data); >| ^~ > net/nfs.c: In function ‘nfs_readlink_reply’: > net/nfs.c:631:46: error: taking address of packed member of ‘struct > rpc_t’ may result in an unaligned pointer value > [-Werror=address-of-packed-member] >631 |nfs3_get_attributes_offset(rpc_pkt.u.reply.data); >| ~~~^ >LD drivers/block/built-in.o > net/nfs.c: In function ‘nfs_read_reply’: > net/nfs.c:692:46: error: taking address of packed member of ‘struct > rpc_t’ may result in an unaligned pointer value > [-Werror=address-of-packed-member] >692 |nfs3_get_attributes_offset(rpc_pkt.u.reply.data); >| ~~~^ > > Best regards > > Heinrich > ___ > U-Boot mailing list > U-Boot@lists.denx.de > https://lists.denx.de/listinfo/u-boot ___ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot
[U-Boot] [BUG] net: nfs: -Werror=address-of-packed-member
Hello Joe, GCC 9.2.1 (of Debian Bullseye) produces the warnings below when building pine64-lts_defconfig. Is it really necessary to define struct rpc_t as packed? The structure is composed out of uint32_t only. So shouldn't it be naturally packed without the attribute? net/nfs.c: In function ‘rpc_req’: net/nfs.c:199:18: error: taking address of packed member of ‘struct rpc_t’ may result in an unaligned pointer value [-Werror=address-of-packed-member] 199 | p = (uint32_t *)&(rpc_pkt.u.call.data); | ^~ net/nfs.c: In function ‘nfs_readlink_reply’: net/nfs.c:631:46: error: taking address of packed member of ‘struct rpc_t’ may result in an unaligned pointer value [-Werror=address-of-packed-member] 631 |nfs3_get_attributes_offset(rpc_pkt.u.reply.data); | ~~~^ LD drivers/block/built-in.o net/nfs.c: In function ‘nfs_read_reply’: net/nfs.c:692:46: error: taking address of packed member of ‘struct rpc_t’ may result in an unaligned pointer value [-Werror=address-of-packed-member] 692 |nfs3_get_attributes_offset(rpc_pkt.u.reply.data); | ~~~^ Best regards Heinrich ___ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot
