pointer being freed was not allocated

[omartijn]

I'm trying out mimalloc, and immediately run into an issue, with the following test code. I've tried both with the latest master and with v2.1.7.

#include <algorithm>
#include <chrono>
#include <functional>
#include <iostream>
#include <thread>
#include <vector>

int main() {
    std::vector<std::unique_ptr<std::size_t>> numbers(1024 * 1024 * 100);
    std::vector<std::thread> threads(1);

    std::atomic<std::size_t> index{};

    auto start = std::chrono::system_clock::now();

    for (auto& thread : threads) {
        thread = std::thread{[&index, &numbers]() {
            while (true) {
                auto i = index.fetch_add(1, std::memory_order_relaxed);
                if (i >= numbers.size()) return;

                numbers[i] = std::make_unique<std::size_t>(i);
            }
        }};
    }

    for (auto& thread : threads) thread.join();

    auto end = std::chrono::system_clock::now();

    auto duration =
        std::chrono::duration_cast<std::chrono::milliseconds>(end - start);
    std::cout << "Running on " << threads.size() << " threads took " << duration
              << std::endl;
}

Compiling this on macOS, like this:

c++ -std=c++20 -g -Wall -Wextra -L/Users/martijn/test -lmimalloc -o allocate allocate.cpp

leads to the following output when run:

allocate(16926,0x16d067000) malloc: *** error for object 0x3ff8c010020: pointer being freed was not allocated
allocate(16926,0x16d067000) malloc: *** set a breakpoint in malloc_error_break to debug

[taco-paco]

Also ran into the same issue, it looks something goes wrong on thread destruction. Simplified version like this crashed for me with familiar:

test(96681,0x16b247000) malloc: *** error for object 0x20000001900: pointer being freed was not allocated
test(96681,0x16b247000) malloc: *** set a breakpoint in malloc_error_break to debug

#include <thread>

void asd() {}
int main() {
    std::thread thread(asd);
    thread.join();

    return 0;
}

mimalloc compiled via:

cmake -DMI_BUILD_STATIC=ON -DMI_BUILD_SHARED=OFF -DMI_BUILD_TESTS=OFF \
    -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX="/usr/local/mimalloc" ..

and then statically linked with the code above.

I'm on macOS 14.3 (23D56) running on arm64

[daanx]

Looking into this. I can repro the second example -- it looks it has to do with zone initialization as it works when using a dynamic library to override and use env DYLD_INSERT_LIBRARIES=./libmimalloc-debug.dylib ./a.out .

Also, if you link with the static object file it also works,

clang++ --std=c++20 -I../../include -g ./mimalloc-debug.o ../../test/main-override.cpp

Here it is best to compile mimalloc with -DMI_USE_CXX=ON or otherwise it triggers assertion failures.

Mmm, usually object files take precedence when resolving function names over library names so it may be a particular function is not overridden correctly with an archive. We may want to advice to not use a static library on MacOS (but the static object file or dylib). I'll try to figure out which function(s) is/are causing the issue.