运行ocsigen报链接错误：找不到dllssl_threads_stubs.so文件

Hey there, let's tackle this ocsigenserver + OpenSSL dynamic library issue together! Your hunch about forcing build flags is totally on the right track—this kind of library path mismatch is super common on macOS, especially with brew-installed dependencies. Let's break down the steps to fix it:

First, let's make sure we're pointing at the right OpenSSL installation. Run this to get brew's OpenSSL location:

brew --prefix openssl

You'll get something like /usr/local/opt/openssl@3 (varies by version). Next, check if opam's openssl package is linked to this path:

opam show -v openssl

Look for build or flags sections in the output. If it's not pointing to your brew path, reinstall the opam package with explicit OpenSSL location:

opam reinstall openssl --with-openssl=$(brew --prefix openssl)

If the above doesn't resolve the issue, your idea to inject compile/link flags is exactly what we need. Here are two ways to do this:

Option 1: Pass Flags Through Opam Reinstall #

Set environment variables before reinstalling ocsigenserver to tell the compiler where to find OpenSSL:

export CFLAGS="-I$(brew --prefix openssl)/include"
export LDFLAGS="-L$(brew --prefix openssl)/lib -lssl -lcrypto"
opam reinstall ocsigenserver

This ensures the build process picks up the correct headers and libraries from your brew installation.

Option 2: Manual Source Compilation (If You're Building From Git/Source) #

If you're compiling ocsigenserver directly from source, pass the flags during configure:

CFLAGS="-I$(brew --prefix openssl)/include" LDFLAGS="-L$(brew --prefix openssl)/lib -lssl -lcrypto" ./configure
make && make install

Some builds might support a direct --with-openssl flag too:

./configure --with-openssl=$(brew --prefix openssl)
make && make install

After rebuilding, confirm ocsigenserver is using the correct OpenSSL libraries with otool (macOS's equivalent of ldd):

otool -L $(which ocsigenserver) | grep ssl

You should see a path pointing to your brew-installed OpenSSL (like /usr/local/opt/openssl@3/lib/libssl.3.dylib). If it's still pointing to the system default, fix it with install_name_tool:

install_name_tool -change /usr/lib/libssl.dylib $(brew --prefix openssl)/lib/libssl.dylib $(which ocsigenserver)
install_name_tool -change /usr/lib/libcrypto.dylib $(brew --prefix openssl)/lib/libcrypto.dylib $(which ocsigenserver)

If you just want to verify the fix works before making permanent changes, add brew's OpenSSL path to your dynamic library lookup temporarily:

export DYLD_LIBRARY_PATH=$(brew --prefix openssl)/lib:$DYLD_LIBRARY_PATH
ocsigenserver

If this runs without errors, add the export line to your shell config (~/.zshrc or ~/.bashrc) to make it permanent.

内容的提问来源于stack exchange，提问作者Kristopher Micinski