I made some progress in getting Stan to read input data directly from MATLAB’s workspace. I am however struggling with linking the libraries into main code. I put together a separate, simple test code to read the variables and store them in var_i_ and var_r_ like vectors and it works OK with the options below:
g++ -g -std=c++1y -pthread -ID:/Matlab/R2022b_x64/extern/include -LD:/Matlab/R2022b_x64/extern/bin/win64 read_struct.cpp -lMatlabEngine -lMatlabDataArray -o out.exe
The problems start when I transfer the code into Stan’s source. I boiled it down to a simple mod to main.cpp which still causes Segmentation fault. I suspect the problem is related to the way/order I link dynamic libraries but I am getting to the point when overwhelmed with the complexity.
I understand this is not the mainstream activity for Stan developers but I’d really appreciate if anybody could give me some hints where to look in order to identify the problem. Some details are below:
I modified cmdstan/make/local
# Adding other arbitrary C++ compiler flags
CXXFLAGS += -funroll-loops
CXXFLAGS += -Wno-nonnull
CXXFLAGS += -Wno-ignored-attributes
CXXFLAGS += -g -pthread
CXXFLAGS += -ID:/Matlab/R2022b_x64/extern/include
PRECOMPILED_HEADERS = false
TBB_CXXFLAGS= -U__MSVCRT_VERSION__ -D__MSVCRT_VERSION__=0x0E00
LDFLAGS += -LD:/Matlab/R2022b_x64/extern/bin/win64
LDLIBS += -lMatlabEngine -lMatlabDataArray -lpthread
and cmdstan/src/cmdstan/main.cpp
#include <cmdstan/command.hpp>
#include <stan/services/error_codes.hpp>
#include "MatlabEngine.hpp"
void findMAT() {
using namespace matlab::engine;
std::vector<String> names = findMATLAB();
}
int main(int argc, const char *argv[]) {
findMAT();
}
gdb fault and stack trace:
(gdb) s
0x00007ff66f84b1e3 in (anonymous namespace)::initSession ()
at D:/Matlab/R2022b_x64/extern/include/MatlabEngine/detail/engine_factory_impl.hpp:20
20 cpp_engine_create_session();
(gdb) bt 10
#0 0x00007ff66f84b1e3 in (anonymous namespace)::initSession ()
at D:/Matlab/R2022b_x64/extern/include/MatlabEngine/detail/engine_factory_impl.hpp:20
#1 matlab::engine::findMATLAB[abi:cxx11]() ()
at D:/Matlab/R2022b_x64/extern/include/MatlabEngine/detail/engine_factory_impl.hpp:54
#2 0x00007ff66f971118 in findMAT () at src/cmdstan/main.cpp:8
#3 main (argc=<optimized out>, argv=<optimized out>) at src/cmdstan/main.cpp:12
(gdb) s
The specified procedure could not be found.
Thread 1 received signal SIGSEGV, Segmentation fault.
0x0000000000000000 in ?? ()
(gdb) info sharedlibrary
From To Syms Read Shared Object Library
0x00007ffdbf131000 0x00007ffdbf327548 Yes (*) C:\WINDOWS\SYSTEM32\ntdll.dll
0x00007ffdbe841000 0x00007ffdbe8fe310 Yes (*) C:\WINDOWS\System32\kernel32.dll
0x00007ffdbc891000 0x00007ffdbcb69990 Yes (*) C:\WINDOWS\System32\KernelBase.dll
0x00007ffdbcf11000 0x00007ffdbd00faf8 Yes (*) C:\WINDOWS\System32\ucrtbase.dll
0x00007ffdb9591000 0x00007ffdb95a50c8 Yes (*) D:\Matlab\R2022b_x64\extern\bin\win64\libMatlabEngine.dll
0x00007ffdb88e1000 0x00007ffdb893b6dc Yes D:\Stan\cmdstan\stan\lib\stan_math\lib\tbb\tbb.dll
0x00007ffda4c71000 0x00007ffda4cfc830 Yes (*) C:\WINDOWS\SYSTEM32\msvcp140.dll
0x00007ffda4c41000 0x00007ffda4c4b13c Yes (*) C:\WINDOWS\SYSTEM32\vcruntime140_1.dll
0x00007ffda4c51000 0x00007ffda4c6a1a0 Yes (*) C:\WINDOWS\SYSTEM32\vcruntime140.dll
0x00007ffdb8d81000 0x00007ffdb8dba084 Yes D:\Stan\cmdstan\stan\lib\stan_math\lib\tbb\tbbmalloc.dll
(*): Shared library is missing debugging information.
Both my stand alone C++ code and unmodified Stan compile and run with no problems. I am working on Win10 with g++ v10.3.0 in UCRT64 environment.