Processor with SSE2 support 
Boost ≥ 1.56
MySQL ≥ 5.1.0 
OpenSSL = 1.0.x
CMake ≥ 3.2.0
GCC ≥ 4.9.3 or Clang  ≥ 3.5 (heavy recommended, specially on master branch)
zlib ≥ 1.2.7

Note: 
While compiling you may get one error like: "c++: internal compiler error: Killed (program cc1plus)" the reasons of this can be:

Low ram/swap amount: increase ram/swap to a minimum of 2GB of ram and 2GB of swap or decrease the amount of make -j to 1 (more concurrent compile threads = more memory usage). (you can get this using VPS servers)
SELinux/grsecurity/Hardened kernel: Kernels that use ASLR as a security measure tend to mess up GCC's precompiled header implementation. Try using an unhardened kernel (without ASLR), or compiling using clang, or gcc without pch. (you can get this issue when using OVH hosting).

If you plan to run compile and run TrinityCore on a Linux machine and the World of Warcraft client on a separate Windows PC, you will also need to compile it on the Window PC, so that you have a Windows "connection_patcher.exe" binary, which needs to be run on the machine where the client will run.

Fedora 26 ships with OpenSSL 1.1.x which can't be used for building TrinityCore. Luckilly, OpenSSL 1.0.x branch is shipped in the package named 'compat-openssl10-devel'. To install it, issue command 'dnf install --allowerasing compat-openssl10-devel'. Note that this will remove already installed openssl-devel package.