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| author | Filipe David Manana <[email protected]> | 2011-09-01 02:05:05 +0100 |
|---|---|---|
| committer | Filipe David Manana <[email protected]> | 2011-09-02 00:35:48 -0700 |
| commit | 03d8c2877342d5ed57596330a61ec0374092f136 (patch) | |
| tree | dc4f32655af4b0ab0fdd7faa30a1092b87bc65b7 | |
| parent | eb4aa9b65c8b50597ed8fae092555145e466e1dc (diff) | |
| download | otp-03d8c2877342d5ed57596330a61ec0374092f136.tar.gz otp-03d8c2877342d5ed57596330a61ec0374092f136.tar.bz2 otp-03d8c2877342d5ed57596330a61ec0374092f136.zip | |
Fix enif_compare on 64bits machines
In 64bits machines the Sint type has a size of 8 bytes,
while on 32bits machines it has a 4 bytes size.
enif_compare was ignoring this and therefore returning
incorrect values when the result of the CMP function
(which returns a Sint value) doesn't fit in 4 bytes.
For example, passing the operands -1294536544000 and
-1178704800000 to enif_compare would trigger the bug.
| -rw-r--r-- | erts/emulator/beam/erl_nif.c | 10 | ||||
| -rw-r--r-- | erts/emulator/test/nif_SUITE.erl | 6 |
2 files changed, 15 insertions, 1 deletions
diff --git a/erts/emulator/beam/erl_nif.c b/erts/emulator/beam/erl_nif.c index d9b1a8e89d..6e7ac43676 100644 --- a/erts/emulator/beam/erl_nif.c +++ b/erts/emulator/beam/erl_nif.c @@ -578,7 +578,15 @@ int enif_is_identical(Eterm lhs, Eterm rhs) int enif_compare(Eterm lhs, Eterm rhs) { - return CMP(lhs,rhs); + Sint result = CMP(lhs,rhs); + + if (result < 0) { + return -1; + } else if (result > 0) { + return 1; + } + + return result; } int enif_get_tuple(ErlNifEnv* env, Eterm tpl, int* arity, const Eterm** array) diff --git a/erts/emulator/test/nif_SUITE.erl b/erts/emulator/test/nif_SUITE.erl index 2867e8e2e4..f6344791f1 100644 --- a/erts/emulator/test/nif_SUITE.erl +++ b/erts/emulator/test/nif_SUITE.erl @@ -281,6 +281,12 @@ types(Config) when is_list(Config) -> end, int_list()), ?line verify_tmpmem(TmpMem), + ?line true = (compare(-1294536544000, -1178704800000) < 0), + ?line true = (compare(-1178704800000, -1294536544000) > 0), + ?line true = (compare(-295147905179352825856, -36893488147419103232) < 0), + ?line true = (compare(-36893488147419103232, -295147905179352825856) > 0), + ?line true = (compare(-29514790517935282585612345678, -36893488147419103232) < 0), + ?line true = (compare(-36893488147419103232, -29514790517935282585612345678) > 0), ok. int_list() -> |