Reported by Feng Feng <f.feng@outlook.com> in https://www.ginac.de/pipermail/ginac-list/2021-December/002368.html --- check/exam_relational.cpp | 17 +++++++++++++++++ ginac/relational.cpp | 4 ++-- 2 files changed, 19 insertions(+), 2 deletions(-) diff --git a/check/exam_relational.cpp b/check/exam_relational.cpp index 3b652b05..f66911f3 100644 --- a/check/exam_relational.cpp +++ b/check/exam_relational.cpp @@ -94,6 +94,21 @@ static unsigned exam_relational_possymbol() return result; } +// Comparisons should maintain ordering invariants +static unsigned exam_relational_order() +{ + unsigned result = 0; + numeric i = 1ll<<32, j = i+1; + symbol a; + relational x = i==a, y = j==a; + if (x.compare(y) != -y.compare(x)) { + clog << "comparison should be antisymmetric." << endl; + result += 1; + } + + return result; +} + // Very simple arithmetic should be supported, too. static unsigned exam_relational_arith() { @@ -125,10 +140,12 @@ unsigned exam_relational() result += exam_relational_elementary(); cout << '.' << flush; result += exam_relational_possymbol(); cout << '.' << flush; result += exam_relational_arith(); cout << '.' << flush; + result += exam_relational_order(); cout << '.' << flush; return result; } + int main(int argc, char** argv) { return exam_relational(); diff --git a/ginac/relational.cpp b/ginac/relational.cpp index 599a2635..dbc541a3 100644 --- a/ginac/relational.cpp +++ b/ginac/relational.cpp @@ -223,8 +223,8 @@ int relational::compare_same_type(const basic & other) const return (o < oth.o) ? -1 : 1; break; } - const int lcmpval = lh.compare(oth.rh); - return (lcmpval!=0) ? lcmpval : rh.compare(oth.lh); + const int lcmpval = lh.compare(oth.lh); + return (lcmpval!=0) ? lcmpval : rh.compare(oth.rh); } bool relational::match_same_type(const basic & other) const -- 2.34.1