Fix FTBFS on i686-linux due to rounding issue (see references). Fixes Guix bug #22049 (see below). Copied from Debian. Source: https://sources.debian.net/src/ilmbase/2.2.0-11/debian/patches/testBoxAlgo.patch/ https://sources.debian.net/src/ilmbase/2.2.0-11/debian/patches/testBox.patch/ References: https://lists.nongnu.org/archive/html/openexr-devel/2015-12/msg00001.html https://debbugs.gnu.org/cgi/bugreport.cgi?bug=22049 https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=815712 https://anonscm.debian.org/cgit/pkg-phototools/ilmbase.git/commit/?id=ab28bb45cdad8adc32e345b777ab8e692b1d9a9c --- Subject: testBoxAlgo: allow fuzzy match of b12 == b2 From: Steven Chamberlain Date: Wed, 24 Feb 2016 01:04:11 +0000 Also fix a pre-existing typo. Index: ilmbase/ImathTest/testBoxAlgo.cpp =================================================================== --- ilmbase.orig/ImathTest/testBoxAlgo.cpp +++ ilmbase/ImathTest/testBoxAlgo.cpp @@ -886,10 +886,11 @@ boxMatrixTransform () assert (approximatelyEqual (b2.min, b4.min, e)); assert (approximatelyEqual (b2.max, b4.max, e)); - assert (approximatelyEqual (b3.max, b4.max, e)); + assert (approximatelyEqual (b3.min, b4.min, e)); assert (approximatelyEqual (b3.max, b4.max, e)); - assert (b21 == b2); + assert (approximatelyEqual (b2.min, b21.min, e)); + assert (approximatelyEqual (b2.max, b21.max, e)); assert (b31 == b3); M[0][3] = 1; --- Subject: testBox: allow fuzzy comparison of floats, doubles From: Steven Chamberlain Date: Wed, 24 Feb 2016 01:10:11 +0000 Allow for inexact values, as long as the error is smaller than the epsilon of the data type. On 32-bit x86, allow even greater discrepency at double precision, due to possible double-rounding. See https://lists.nongnu.org/archive/html/openexr-devel/2015-12/msg00001.html Index: ilmbase/ImathTest/testBox.cpp =================================================================== --- ilmbase.orig/ImathTest/testBox.cpp +++ ilmbase/ImathTest/testBox.cpp @@ -47,6 +47,58 @@ using namespace IMATH_INTERNAL_NAMESPACE namespace { +template +bool +approximatelyEqual (const T &p1, const T &p2) +{ + /* int and short should be exact */ + return (p1 == p2); +} + +bool +approximatelyEqual (const Vec2 &p1, const Vec2 &p2) +{ + float e = limits::epsilon(); + float m = 0; + + for (int i = 0; i < 2; ++i) + { + m = max (m, abs (p1[i])); + m = max (m, abs (p2[i])); + } + + for (int i = 0; i < 2; ++i) + if (!equalWithAbsError (p1[i], p2[i], m * e)) + return false; + + return true; +} + +bool +approximatelyEqual (const Vec2 &p1, const Vec2 &p2) +{ +#if defined(__i386__) || defined(_M_IX86) + /* double-rounding on 32-bit x86 may cause larger error: + use epsilon of float rather than double */ + double e = limits::epsilon(); +#else + double e = limits::epsilon(); +#endif + double m = 0; + + for (int i = 0; i < 2; ++i) + { + m = max (m, abs (p1[i])); + m = max (m, abs (p2[i])); + } + + for (int i = 0; i < 2; ++i) + if (!equalWithAbsError (p1[i], p2[i], m * e)) + return false; + + return true; +} + // // Test case generation utility - create a vector of IMATH_INTERNAL_NAMESPACE::Vec{2,3,4} // with all permutations of integers 1..T::dimensions(). @@ -250,7 +302,8 @@ testExtendByPoint(const char *type) IMATH_INTERNAL_NAMESPACE::Box b; b.extendBy(p); - assert(b.min == p && b.max == p); + assert (approximatelyEqual (b.min, p)); + assert (approximatelyEqual (b.max, p)); } // @@ -283,7 +336,8 @@ testExtendByPoint(const char *type) b.extendBy(p); - assert(b.min == min && b.max == max); + assert (approximatelyEqual (b.min, min)); + assert (approximatelyEqual (b.max, max)); } } } @@ -358,7 +412,8 @@ testExtendByBox(const char *type) } b.extendBy(IMATH_INTERNAL_NAMESPACE::Box(p0, p1)); - assert(b.min == min && b.max == max); + assert (approximatelyEqual (b.min, min)); + assert (approximatelyEqual (b.max, max)); } } }