From dde8b3609b40a5e9073a7638d492b8c29af2e24c Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Thu, 29 Sep 2011 13:14:51 +0000 Subject: Change random seeds to 64bit and drop re-crcing I had some trouble with random build failures in a large LTO project and it turned out to be random seed collisions in a highly parallel build (thanks to Honza for suggesting that) There were multiple problems: - The way to generate the random seed is not very random (milliseconds time plus pid) and prone to collisions on highly parallel builds - It's only 32bit - Several users take the existing ascii seed and re-CRC32 it again, which doesn't exactly improve it. This patch changes that to: - Always use 64bit seeds as numbers (no re-crcing) - Change all users to use HOST_WIDE_INT - When the user specifies a random seed it's still crc32ed, but only in this case. Passes bootstrap + testsuite on x86_64-linux. gcc/cp: 2011-09-26 Andi Kleen * repo.c (finish_repo): Use HOST_WIDE_INT_PRINT_HEX_PURE. gcc/: 2011-09-26 Andi Kleen * hwint.h (HOST_WIDE_INT_PRINT_HEX_PURE): Add. * lto-streamer.c (lto_get_section_name): Remove crc32_string. Handle numerical random seed. * lto-streamer.h (lto_file_decl_data): Change id to unsigned HOST_WIDE_INT. * toplev.c (random_seed): Add. (init_random_seed): Change for numerical random seed. (get_random_seed): Return as HOST_WIDE_INT. (set_random_seed): Crc32 existing string. * toplev.h (get_random_seed): Change to numercal return. * tree.c (get_file_function_name): Remove CRC. Handle numerical random seed. gcc/lto/: 2011-09-26 Andi Kleen * lto.c (lto_resolution_read): Remove id dumping. (lto_section_with_id): Turn id HOST_WIDE_ID. (create_subid_section_table): Dito. From-SVN: r179347 --- gcc/lto-streamer.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'gcc/lto-streamer.h') diff --git a/gcc/lto-streamer.h b/gcc/lto-streamer.h index 190d6a3..2564bd2 100644 --- a/gcc/lto-streamer.h +++ b/gcc/lto-streamer.h @@ -552,7 +552,7 @@ struct GTY(()) lto_file_decl_data struct lto_file_decl_data *next; /* Sub ID for merged objects. */ - unsigned id; + unsigned HOST_WIDE_INT id; /* Symbol resolutions for this file */ VEC(ld_plugin_symbol_resolution_t,heap) * GTY((skip)) resolutions; -- cgit v1.1