Removing OpenSSL 3.0 devel so C++ compiles on Linux - c++

Question

I'm on Ubuntu 22.04 and compiling this C++ Github pull request:
https://github.com/ftexchange/ftx/pull/13
However, the PR contains a compile error.
Somebody posted to fix the error OpenSSL 3.0 devel version must be "removed":
It seems like the compiler was using OpenSSL 3.0 devel version, I had
to remove that
How do I achieve this?

Answer 1

This is what I did on Ubuntu 22.04 LTS.
$ sudo apt install libboost-dev libssl-dev
$ git clone --recursive --branch openssl-1.1 https://github.com/arf-labs-ou/ftx.git
$ cmake -G Ninja -S ftx/cpp -B build -DCMAKE_BUILD_TYPE=Release
$ cmake --build build
Trying to build at this point will trip deprecation warnings when compiling against the system OpenSSL 3. But because ftx has done the extremely inadvisable thing of hard-coding -Werror in their build, this is promoted to a spurious error. Deprecated doesn't mean "won't work today"; it means "upstream must fix". You are not upstream, so this ought not affect you, but, alas, low-quality build code is not a great surprise.
We will hack around this by wrapping the compiler with a shell script that deletes warning flags from the command line. Create a file called no-warnings.sh:
#!/bin/bash
ARGS=()
for arg in "$#"; do
if [[ ! "$arg" =~ ^-W ]]; then
ARGS+=("$arg")
fi
done
"${ARGS[#]}"
Now let's inject it into the build via the CMAKE_CXX_COMPILER_LAUNCHER hook:
$ chmod +x no-warnings.sh
$ rm -rf build
$ cmake -G Ninja -S ftx/cpp/ -B build -DCMAKE_BUILD_TYPE=Release -DCMAKE_CXX_COMPILER_LAUNCHER=$PWD/no-warnings.sh
$ cmake --build build/
This should work but, unfortunately, even this wasn't enough to build successfully. The code itself has a type error! I wonder if something changed between Boost 1.71 and 1.74. Anyway, I applied the following patch:
diff --git a/cpp/src/util/HTTP.cc b/cpp/src/util/HTTP.cc
index 30e0277..2d043f2 100644
--- a/cpp/src/util/HTTP.cc
+++ b/cpp/src/util/HTTP.cc
## -100,8 +100,8 ## void HTTPSession::authenticate(http::request<http::string_body>& req)
std::string path(req.target());
std::string body(req.body());
- long ts = get_ms_timestamp(current_time()).count();
- std::string data = std::to_string(ts) + method + path;
+ auto ts = std::to_string(get_ms_timestamp(current_time()).count());
+ std::string data = ts + method + path;
if (!body.empty()) {
data += body;
}
And now the above commands produce a successful build. The example programs run and produce reasonable output, as well.