algebraic_match_mul_with_mul() iterates over operands of mul, that is for (size_t i=0; i<e.nops(); ++i) However, the size of arrays (`vectors' in STL speak) passed to this function is seq.size(), which is nops() - 1 for any mul object. Thus algebraic_match_mul_with_mul() accesses beyond the arrays limit. Usually it's not a problem, since any reasonable implementation of std::vector<bool> packs booleans into ints (or longs). However, some STL implementations (in particular, the one shipped with msvc) are more picky, and access beyond the vector<bool> limits results in a segfault. Therefore let's play safe and allocate proper number of elements (that is, nops()) for those arrays (subsed and currsubsed). Thanks to Jan Rheinländer for a bug report. --- ginac/mul.cpp | 12 +++++++----- 1 files changed, 7 insertions(+), 5 deletions(-) diff --git a/ginac/mul.cpp b/ginac/mul.cpp index dfda410..3733bc4 100644 --- a/ginac/mul.cpp +++ b/ginac/mul.cpp @@ -729,6 +729,9 @@ bool algebraic_match_mul_with_mul(const mul &e, const ex &pat, exmap& repls, int factor, int &nummatches, const std::vector<bool> &subsed, std::vector<bool> &matched) { + GINAC_ASSERT(subsed.size() == e.nops()); + GINAC_ASSERT(matched.size() == e.nops()); + if (factor == (int)pat.nops()) return true; @@ -760,8 +763,8 @@ bool mul::has(const ex & pattern, unsigned options) const if(is_a<mul>(pattern)) { exmap repls; int nummatches = std::numeric_limits<int>::max(); - std::vector<bool> subsed(seq.size(), false); - std::vector<bool> matched(seq.size(), false); + std::vector<bool> subsed(nops(), false); + std::vector<bool> matched(nops(), false); if(algebraic_match_mul_with_mul(*this, pattern, repls, 0, nummatches, subsed, matched)) return true; @@ -771,8 +774,7 @@ bool mul::has(const ex & pattern, unsigned options) const ex mul::algebraic_subs_mul(const exmap & m, unsigned options) const { - std::vector<bool> subsed(seq.size(), false); - exvector subsresult(seq.size()); + std::vector<bool> subsed(nops(), false); ex divide_by = 1; ex multiply_by = 1; @@ -781,7 +783,7 @@ ex mul::algebraic_subs_mul(const exmap & m, unsigned options) const if (is_exactly_a<mul>(it->first)) { retry1: int nummatches = std::numeric_limits<int>::max(); - std::vector<bool> currsubsed(seq.size(), false); + std::vector<bool> currsubsed(nops(), false); exmap repls; if(!algebraic_match_mul_with_mul(*this, it->first, repls, 0, nummatches, subsed, currsubsed)) -- 1.7.1