diff options
| -rw-r--r-- | sv.c | 72 |
1 files changed, 46 insertions, 26 deletions
@@ -1242,6 +1242,34 @@ struct body_details { #endif #define NOARENA FALSE +/* A macro to work out the offset needed to subtract from a pointer to (say) + +typedef struct { + STRLEN xpv_cur; + STRLEN xpv_len; +} xpv_allocated; + +to make its members accessible via a pointer to (say) + +struct xpv { + NV xnv_nv; + STRLEN xpv_cur; + STRLEN xpv_len; +}; + +*/ + +#define relative_STRUCT_OFFSET(longer, shorter, member) \ + STRUCT_OFFSET(shorter, member) - STRUCT_OFFSET(longer, member) + +/* Calculate the length to copy. Specifically work out the length less any + final padding the compiler needed to add. See the comment in sv_upgrade + for why copying the padding proved to be a bug. */ + +#define copy_length(type, last_member) \ + STRUCT_OFFSET(type, last_member) \ + + sizeof (((type*)SvANY((SV*)0))->last_member) + static const struct body_details bodies_by_type[] = { {0, 0, 0, FALSE, NONV, NOARENA}, /* IVs are in the head, so the allocation size is 0 */ @@ -1253,24 +1281,20 @@ static const struct body_details bodies_by_type[] = { {0, 0, 0, FALSE, NONV, NOARENA}, /* 8 bytes on most ILP32 with IEEE doubles */ {sizeof(xpv_allocated), - STRUCT_OFFSET(XPV, xpv_len) + sizeof (((XPV*)SvANY((SV*)0))->xpv_len) - + STRUCT_OFFSET(xpv_allocated, xpv_cur) - STRUCT_OFFSET(XPV, xpv_cur), - + STRUCT_OFFSET(xpv_allocated, xpv_cur) - STRUCT_OFFSET(XPV, xpv_cur) - , FALSE, NONV, HASARENA}, + copy_length(XPV, xpv_len) + + relative_STRUCT_OFFSET(XPV, xpv_allocated, xpv_cur), + + relative_STRUCT_OFFSET(XPV, xpv_allocated, xpv_cur), + FALSE, NONV, HASARENA}, /* 12 */ {sizeof(xpviv_allocated), - STRUCT_OFFSET(XPVIV, xiv_u) + sizeof (((XPVIV*)SvANY((SV*)0))->xiv_u) - + STRUCT_OFFSET(xpviv_allocated, xpv_cur) - STRUCT_OFFSET(XPVIV, xpv_cur), - + STRUCT_OFFSET(xpviv_allocated, xpv_cur) - STRUCT_OFFSET(XPVIV, xpv_cur) - , FALSE, NONV, HASARENA}, + copy_length(XPVIV, xiv_u) + + relative_STRUCT_OFFSET(XPVIV, xpviv_allocated, xpv_cur), + + relative_STRUCT_OFFSET(XPVIV, xpviv_allocated, xpv_cur), + FALSE, NONV, HASARENA}, /* 20 */ - {sizeof(XPVNV), - STRUCT_OFFSET(XPVNV, xiv_u) + sizeof (((XPVNV*)SvANY((SV*)0))->xiv_u), - 0, FALSE, HADNV, HASARENA}, + {sizeof(XPVNV), copy_length(XPVNV, xiv_u), 0, FALSE, HADNV, HASARENA}, /* 28 */ - {sizeof(XPVMG), - STRUCT_OFFSET(XPVMG, xmg_stash) + sizeof (((XPVMG*)SvANY((SV*)0))->xmg_stash), - 0, FALSE, HADNV, HASARENA}, + {sizeof(XPVMG), copy_length(XPVMG, xmg_stash), 0, FALSE, HADNV, HASARENA}, /* 36 */ {sizeof(XPVBM), sizeof(XPVBM), 0, TRUE, HADNV, HASARENA}, /* 48 */ @@ -1279,20 +1303,16 @@ static const struct body_details bodies_by_type[] = { {sizeof(XPVLV), sizeof(XPVLV), 0, TRUE, HADNV, HASARENA}, /* 20 */ {sizeof(xpvav_allocated), - STRUCT_OFFSET(XPVAV, xmg_stash) - + sizeof (((XPVAV*)SvANY((SV *)0))->xmg_stash) - + STRUCT_OFFSET(xpvav_allocated, xav_fill) - - STRUCT_OFFSET(XPVAV, xav_fill), - STRUCT_OFFSET(xpvav_allocated, xav_fill) - - STRUCT_OFFSET(XPVAV, xav_fill), TRUE, HADNV, HASARENA}, + copy_length(XPVAV, xmg_stash) + + relative_STRUCT_OFFSET(XPVAV, xpvav_allocated, xav_fill), + relative_STRUCT_OFFSET(XPVAV, xpvav_allocated, xav_fill), + TRUE, HADNV, HASARENA}, /* 20 */ {sizeof(xpvhv_allocated), - STRUCT_OFFSET(XPVHV, xmg_stash) - + sizeof (((XPVHV*)SvANY((SV *)0))->xmg_stash) - + STRUCT_OFFSET(xpvhv_allocated, xhv_fill) - - STRUCT_OFFSET(XPVHV, xhv_fill), - STRUCT_OFFSET(xpvhv_allocated, xhv_fill) - - STRUCT_OFFSET(XPVHV, xhv_fill), TRUE, HADNV, HASARENA}, + copy_length(XPVHV, xmg_stash) + + relative_STRUCT_OFFSET(XPVHV, xpvhv_allocated, xhv_fill), + relative_STRUCT_OFFSET(XPVHV, xpvhv_allocated, xhv_fill), + TRUE, HADNV, HASARENA}, /* 76 */ {sizeof(XPVCV), sizeof(XPVCV), 0, TRUE, HADNV, HASARENA}, /* 80 */ |