Description
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What version (or hash if on master) of pybind11 are you using?
2.10.3
Problem description
UPDATE: The following error seems to be related to #3923, which updated the scoped_interpreter constructor to initialize the python interpreter in an isolated environment via PyConfig_InitIsolatedConfig. If I init my own PyConfig object via PyConfig_InitPythonConfig and pass it to the scoped_interpreter constructor, I don't have the error. Thus, the issue is probably just a wrong assumption in how I'm supposed to use scoped_interpreter.
On the latest pybind, I'm trying to use the embedded python in C++.
Specifically, I'm trying to import matplotlib, which was installed to ~/.local/python3.11/site-packages via python -m pip install matplotlib
However, I'm getting the following error when running pybind11::module::import("matplotlib");
terminate called after throwing an instance of 'pybind11::error_already_set'
what(): ModuleNotFoundError: No module named 'matplotlib'
After some debugging, it appears to be due to a difference between pybind 2.9.2 and pybind 2.10.0, as the following snippet has different outputs between the 2 releases:
auto sys = pybind11::module::import("sys");
auto path = sys.attr("path");
pybind11::print(pybind11::str(path));On 2.9.2, the output is:
`['/usr/lib64/python311.zip', '/usr/lib64/python3.11', '/usr/lib64/python3.11/lib-dynload', '~/.local/lib/python3.11/site-packages', '/usr/local/lib64/python3.11/site-packages', '/usr/local/lib/python3.11/site-packages', '/usr/lib64/python3.11/site-packages', '/usr/lib/python3.11/site-packages']`But on 2.10.0, the output is missing a couple paths (namely, the local and .local paths):
`['/usr/lib64/python311.zip', '/usr/lib64/python3.11', '/usr/lib64/python3.11/lib-dynload', '/usr/lib64/python3.11/site-packages', '/usr/lib/python3.11/site-packages']`Environment:
- OS: Fedora 37
- Python: 3.11.1
- Pybind: 2.10.0 and later
- Matplotlib: 3.6.3
- Compiler: gcc 12.2.1
Reproducible example code
#include <pybind11/embed.h>
#include <pybind11/pybind11.h>
int main() {
pybind11::scoped_interpreter guard{};
auto sys = pybind11::module::import("sys");
auto path = sys.attr("path");
pybind11::print(pybind11::str(path));
// fails
auto pyplot = pybind11::module::import("matplotlib");
}
Is this a regression? Put the last known working version here if it is.
Possibly. Worked in 2.9.2