Error bootstrapping on CentOS

[alexreg]

It looks like the bootstrapper does not use cmake3 on CentOS (i.e., CMake 3.x) but instead cmake (i.e., version 2.x). This results in the error CMake 3.4.3 or higher is required. You are running version 2.8.12.2. The fix would seem to be obvious: check for cmake3 before falling back to cmake.

Relevant section of console output:

    Finished release [optimized + debuginfo] target(s) in 49.26s
Copying stage0 std from stage0 (x86_64-unknown-linux-gnu -> x86_64-unknown-linux-gnu / x86_64-unknown-linux-gnu)
Building LLVM for x86_64-unknown-linux-gnu
running: "cmake" "/home/alexreg/src/rust-devel/trait-upcasting/src/llvm-project/llvm" "-DLLVM_ENABLE_ASSERTIONS=ON" "-DLLVM_TARGETS_TO_BUILD=AArch64;ARM;Hexagon;MSP430;Mips;NVPTX;PowerPC;RISCV;Sparc;SystemZ;WebAssembly;X86" "-DLLVM_EXPERIMENTAL_TARGETS_TO_BUILD=" "-DLLVM_INCLUDE_EXAMPLES=OFF" "-DLLVM_INCLUDE_TESTS=OFF" "-DLLVM_INCLUDE_DOCS=OFF" "-DLLVM_INCLUDE_BENCHMARKS=OFF" "-DLLVM_ENABLE_ZLIB=OFF" "-DWITH_POLLY=OFF" "-DLLVM_ENABLE_TERMINFO=OFF" "-DLLVM_ENABLE_LIBEDIT=OFF" "-DLLVM_ENABLE_BINDINGS=OFF" "-DLLVM_ENABLE_Z3_SOLVER=OFF" "-DLLVM_PARALLEL_COMPILE_JOBS=32" "-DLLVM_TARGET_ARCH=x86_64" "-DLLVM_DEFAULT_TARGET_TRIPLE=x86_64-unknown-linux-gnu" "-DLLVM_LINK_LLVM_DYLIB=ON" "-DLLVM_ENABLE_LIBXML2=OFF" "-DLLVM_VERSION_SUFFIX=-rust-dev" "-DPYTHON_EXECUTABLE=/usr/bin/python" "-DCMAKE_INSTALL_MESSAGE=LAZY" "-DCMAKE_C_COMPILER=cc" "-DCMAKE_CXX_COMPILER=c++" "-DCMAKE_C_FLAGS=-ffunction-sections -fdata-sections -fPIC -m64" "-DCMAKE_CXX_FLAGS=-ffunction-sections -fdata-sections -fPIC -m64" "-DCMAKE_INSTALL_PREFIX=/home/alexreg/src/rust-devel/trait-upcasting/build/x86_64-unknown-linux-gnu/llvm" "-DCMAKE_BUILD_TYPE=Release"
CMake Error at CMakeLists.txt:3 (cmake_minimum_required):
  CMake 3.4.3 or higher is required.  You are running version 2.8.12.2


-- Configuring incomplete, errors occurred!
thread 'main' panicked at '
command did not execute successfully, got: exit code: 1

build script failed, must exit now', /home/alexreg/.cargo/registry/src/github.com-1ecc6299db9ec823/cmake-0.1.42/src/lib.rs:861:5
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
	finished in 0.027
failed to run: /home/alexreg/src/rust-devel/trait-upcasting/build/bootstrap/debug/bootstrap -i test src/test/ui/traits/trait-upcasting
Build completed unsuccessfully in 0:01:59

[Mark-Simulacrum]

I would accept a PR doing what you suggest is obvious.

[alexreg]

Also, is there a reason that the bootstrapping script uses python rather than python3?

[Mark-Simulacrum]

We have a number of fallbacks, but it was my perspective that we should prefer python and fallback to python3, at least for now; I suspect systems may prefer to install to python rather than python3. We work with both 2.7 and 3.

[alexreg]

Okay, thanks for clarifying. Makes detecting whether cmake3 exists slightly more annoying, but not a huge deal.

[jyn514]

@alexreg on CentOS 8, cmake --version gives cmake version 3.11.4. What version of CentOS are you on?

[jyn514]

EOL for CentOS 7 is June 30, 2024; if we haven't heard back by then i think this issue should just be closed.