diff options
Diffstat (limited to 'erts/emulator/test/bs_construct_SUITE.erl')
| -rw-r--r-- | erts/emulator/test/bs_construct_SUITE.erl | 28 |
1 files changed, 27 insertions, 1 deletions
diff --git a/erts/emulator/test/bs_construct_SUITE.erl b/erts/emulator/test/bs_construct_SUITE.erl index cadb30e1a4..06f3bc2ff8 100644 --- a/erts/emulator/test/bs_construct_SUITE.erl +++ b/erts/emulator/test/bs_construct_SUITE.erl @@ -911,5 +911,31 @@ append_unit_8(Bin) -> append_unit_16(Bin) -> <<Bin/binary-unit:16,0:1>>. - +bs_add_overflow(Config) -> + case erlang:system_info(wordsize) of + 8 -> + {skip, "64-bit architecture"}; + 4 -> + {'EXIT', {system_limit, _}} = (catch bs_add_overflow_signed()), + {'EXIT', {system_limit, _}} = (catch bs_add_overflow_unsigned()), + ok + end. + +bs_add_overflow_signed() -> + %% Produce a large result of bs_add that, if cast to signed int, would + %% overflow into a negative number that fits a smallnum. + Large = <<0:((1 bsl 30)-1)>>, + <<Large/bits, Large/bits, Large/bits, Large/bits, + Large/bits, Large/bits, Large/bits, Large/bits, + Large/bits>>. + +bs_add_overflow_unsigned() -> + %% Produce a large result of bs_add that goes beyond the limit of an + %% unsigned word. This used to succeed but produced an incorrect result + %% where B =:= C! + A = <<0:((1 bsl 32)-8)>>, + B = <<2, 3>>, + C = <<A/binary,1,B/binary>>, + true = byte_size(B) < byte_size(C). + id(I) -> I. |