commit c8564f2df2a85a753e25bf48b4eefbf8379fe31a
author Calin Juravle <calin@google.com> Thu Mar 27 13:41:06 2014 +0000
committer Calin Juravle <calin@google.com> Fri Mar 28 11:10:01 2014 +0000
tree b0b1e6a7057b6bd1ddeb166d25a06438fa80b775
parent a58b3f78e14500e7b10fc845ef0a6a8309664663

Fix math tests.

Bug: 13657654
Change-Id: I39b2f13b5b3d3e6897618ac3aed49a0a08458dd0

tests/math_test.cpp

diff --git a/tests/math_test.cpp b/tests/math_test.cpp
index 80083fa..c1a9f4f 100644
--- a/tests/math_test.cpp
+++ b/tests/math_test.cpp
@@ -1226,6 +1226,11 @@
   double di;
   double df = modf(123.456, &di);
   ASSERT_DOUBLE_EQ(123.0, di);
+  // ASSERT_DOUBLE uses more decimals than the double precision when performing
+  // the comparison which can result in false failures. And it seems that modf
+  // results are not 100% precise as expected but within the acceptable delta.
+  // Work around this by tweaking the expected value (taken) from the result of
+  // glibc modf).
   ASSERT_DOUBLE_EQ(0.45600000000000307, df);
 }
 
@@ -1233,6 +1238,7 @@
   float fi;
   float ff = modff(123.456f, &fi);
   ASSERT_FLOAT_EQ(123.0f, fi);
+  // See modf comment on why we don't use 0.456f as an excepted value.
   ASSERT_FLOAT_EQ(0.45600128f, ff);
 }
 
@@ -1240,7 +1246,14 @@
   long double ldi;
   long double ldf = modfl(123.456l, &ldi);
   ASSERT_DOUBLE_EQ(123.0l, ldi);
-  ASSERT_DOUBLE_EQ(0.45600000000000002l, ldf);
+  // See modf comment on why we don't use 0.456l as an excepted value when the
+  // modf == modfl. For LP64, where long double != double, modfl algorithm
+  // gives precise results and thus we don't need to tweak the expected value.
+#if defined(__LP64__) || !defined(__BIONIC__)
+  ASSERT_DOUBLE_EQ(0.456l, ldf);
+#else
+  ASSERT_DOUBLE_EQ(0.45600000000000307, ldf);
+#endif // __LP64__ || !__BIONIC__
 }
 
 TEST(math, remquo) {