Bug in gsl_spmatrix_transpose_memcpy

[Gilberto Chavez Martinez]

Bug description: Function
*int gsl_spmatrix_transpose_memcpy(gsl_spmatrix * dest, const gsl_spmatrix
* src)*
is in error when *dest *matrix has data. This can be solved by setting such
matrix to zero, which is not expected when copying from another matrix.
Included is a program that exercises the bug; both matrices are read from
the same text file, also included.

Version: GSL 2.6
Operating System: openSUSE Tumbleweed 20210316
Kernel Version: 5.11.6-1-default
OS Type: 64-bit
Processors: 8 × Intel Core i7-4700MQ CPU @ 2.40GHz
Memory: 15.6 GiB of RAM
GCC version output:
Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/usr/lib64/gcc/x86_64-suse-linux/10/lto-wrapper
OFFLOAD_TARGET_NAMES=nvptx-none:amdgcn-amdhsa
OFFLOAD_TARGET_DEFAULT=1
Target: x86_64-suse-linux
Configured with: ../configure --prefix=/usr --infodir=/usr/share/info
--mandir=/usr/share/man --libdir=/usr/lib64 --libexecd
ir=/usr/lib64 --enable-languages=c,c++,objc,fortran,obj-c++,ada,go,d
--enable-offload-targets=nvptx-none,amdgcn-amdhsa, --wi
thout-cuda-driver --enable-checking=release --disable-werror
--with-gxx-include-dir=/usr/include/c++/10 --enable-ssp --disab
le-libssp --disable-libvtv --enable-cet=auto --disable-libcc1
--enable-plugin --with-bugurl=https://bugs.opensuse.org/ --wit
h-pkgversion='SUSE Linux' --with-slibdir=/lib64 --with-system-zlib
--enable-libstdcxx-allocator=new --disable-libstdcxx-pch
--enable-libphobos --enable-version-specific-runtime-libs
--with-gcc-major-version-only --enable-linker-build-id --enable-li
nux-futex --enable-gnu-indirect-function --program-suffix=-10
--without-system-libunwind --enable-multilib --with-arch-32=x8
6-64 --with-tune=generic --with-build-config=bootstrap-lto-lean
--enable-link-mutex --build=x86_64-suse-linux --host=x86_64-
suse-linux
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 10.2.1 20210303 [revision
85977f624a34eac309f9d77a58164553dfc82975] (SUSE Linux)

matrix.txt
Description: Text document

main_sparse_bug.c
Description: Text Data