SparseMatrix reallocation throws std::bad_alloc when StorageIndex > Eigen::Index
Submitted by Robin Deits
Assigned to Nobody
Link to original bugzilla bug (#1706)
Version: 3.3 (current stable)
Description
It appears that the internal resize methods for SparseMatrix spuriously throw std::bad_alloc when using a SparseMatrix whose StorageIndex is of a wider integer type than Eigen::Index.
For example, consider the following snippet, in which we construct a SparseMatrix using 64-bit StorageIndex in a context where Eigen::Index is a 32-bit integer:
#define EIGEN_DEFAULT_DENSE_INDEX_TYPE int32_t
#include <Eigen/Core>
#include <Eigen/Sparse>
int main() {
Eigen::SparseMatrix<double, Eigen::ColMajor, int64_t> mat(5, 5);
for (int i = 0; i < 5; i++) {
for (int j = 0; j < 5; j++) {
mat.coeffRef(i, j) = 1;
}
}
return 0;
}
Compiling this with:
g++ main.cpp -o main -Ieigen-3.3.7 -std=c++11
(assuming the Eigen sources live in ./eigen-3.3.7) and running it with ./main will abort with:
terminate called after throwing an instance of 'std::bad_alloc'
what(): std::bad_alloc
Aborted (core dumped)
The issue appears to stem from the following line in SparseCore/CompressedStorage.h:
Index realloc_size = (std::min<Index>)(NumTraits<StorageIndex>::highest(), size + Index(reserveSizeFactor*double(size)));
when StorageIndex is wider than Index, this results in realloc_size being set to -1, which triggers the internal::throw_std_bad_alloc() on the next line.