From d73423cdba178c166f25e00a4608ccc8d0465937 Mon Sep 17 00:00:00 2001 From: Sverker Eriksson Date: Tue, 14 Feb 2017 15:53:04 +0100 Subject: erts: Fix round/1 for large floats 1> round(6209607916799025.0). 6209607916799026 Problem: Adding/subtracting 0.5 and large double floats between (1 bsl 52) and (1 bsl 53) does not give reliable results. Solution: Use round() function in math.h. --- erts/emulator/test/guard_SUITE.erl | 1 + erts/emulator/test/num_bif_SUITE.erl | 3 +++ 2 files changed, 4 insertions(+) (limited to 'erts/emulator/test') diff --git a/erts/emulator/test/guard_SUITE.erl b/erts/emulator/test/guard_SUITE.erl index e155e5f49f..54ee710363 100644 --- a/erts/emulator/test/guard_SUITE.erl +++ b/erts/emulator/test/guard_SUITE.erl @@ -317,6 +317,7 @@ guard_bifs(Config) when is_list(Config) -> try_gbif('float/1', Big, float(id(Big))), try_gbif('trunc/1', Float, 387924.0), try_gbif('round/1', Float, 387925.0), + try_gbif('round/1', 6209607916799025.0, 6209607916799025), try_gbif('length/1', [], 0), try_gbif('length/1', [a], 1), diff --git a/erts/emulator/test/num_bif_SUITE.erl b/erts/emulator/test/num_bif_SUITE.erl index d1c9648017..bb85738454 100644 --- a/erts/emulator/test/num_bif_SUITE.erl +++ b/erts/emulator/test/num_bif_SUITE.erl @@ -293,6 +293,9 @@ t_round(Config) when is_list(Config) -> 4294967297 = round(id(4294967296.9)), -4294967296 = -round(id(4294967296.1)), -4294967297 = -round(id(4294967296.9)), + + 6209607916799025 = round(id(6209607916799025.0)), + -6209607916799025 = round(id(-6209607916799025.0)), ok. t_trunc(Config) when is_list(Config) -> -- cgit v1.2.3