------- Comment #1 from ebotcazou at gcc dot gnu dot org 2010-08-27 16:00 ------- I can confirm something similar (an unaligned access) on IA64/Linux:
(botca...@tinto) /nile.build/botcazou/gcc-head/ia64-unknown-linux-gnu $ gcc/gnat1 -quiet assert1.adb -I gcc/ada/rts gnat1(32495): unaligned access to 0x60000fffffffa55c, ip=0x40000000005e8cc1 gnat1(32495): unaligned access to 0x60000fffffffa574, ip=0x40000000005e8cc1 gnat1(32495): unaligned access to 0x60000fffffffa58c, ip=0x40000000005e8cc1 gnat1(32495): unaligned access to 0x60000fffffffa55c, ip=0x40000000005e8cc1 The address points to: Breakpoint 1, sem_aggr.sort_case_table (component_typ=72) at /nile.build/botcazou/gcc-head/src/gcc/ada/sem_aggr.adb:3974 3974 T := Case_Table (K + 1); It started to fail on 08/12 according to: http://gcc.gnu.org/ml/gcc-testresults/2010-08/msg01253.html http://gcc.gnu.org/ml/gcc-testresults/2010-08/msg01253.html Likely triggered/exposed by: 2010-08-12 Richard Guenther <rguent...@suse.de> * tree-flow.h (struct ptr_info_def): Add align and misalign fields. * tree-ssa-alias.c (get_ptr_info): Move ... * tree-ssanames.c (get_ptr_info): ... here. Initialize align and misalign fields conservatively. * tree-ssa-ccp.c (ccp_finalize): From partially constant pointers derive alignment information. (evaluate_stmt): Derive alignment information from memory allocation functions. * tree.h (get_pointer_alignment): Make unsigned. * builtins.c (get_object_alignment): Use alignment information we have computed for pointers. (get_pointer_alignment): Likewise. Make conservative, return and unsigned value. (expand_builtin_strlen): Adjust. (expand_builtin_memcmp): Likewise. (expand_builtin_strcmp): Likewise. (expand_builtin_strncmp): Likewise. (get_builtin_sync_mem): Use at least mode alignment. (fold_builtin_memset): Adjust. (fold_builtin_memory_op): Likewise. * gimple-pretty-print.c (dump_gimple_phi): Alongside alias information also dump pointer alignment knowledge. (dump_gimple_stmt): Likewise. -- ebotcazou at gcc dot gnu dot org changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |ebotcazou at gcc dot gnu dot | |org Status|UNCONFIRMED |NEW Ever Confirmed|0 |1 Last reconfirmed|0000-00-00 00:00:00 |2010-08-27 16:00:30 date| | Summary|[4.6 regression] Ada |[4.6 regression] Ada |bootstrap failure on IRIX |bootstrap failure on IRIX |6.5: SEGV in |6.5: SIGBUS in |sem_aggr.sort_case_table |sem_aggr.sort_case_table http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45421