Revert LTO for mingw on windows.
authorJoost VandeVondele <Joost.VandeVondele@gmail.com>
Sat, 27 Jun 2020 06:23:46 +0000 (08:23 +0200)
committerJoost VandeVondele <Joost.VandeVondele@gmail.com>
Sat, 27 Jun 2020 08:22:27 +0000 (10:22 +0200)
commitca41ee6632368676a2fb98fd2970ac9b183f0aa9
tree8ccb196440d2b440de8bd0a1b9ffa209f2055f7c
parentaecfca2dc2d760df257e18cd6b29d266a3c3e68a
Revert LTO for mingw on windows.

LTO with static linking is still only working with the latest versions of gcc,
causing problems for some devs.

on a modern mingw toolchain LTO optimizations can still be enabled as:

```
CXXFLAGS='-flto' make -j ARCH=x86-64-modern COMP=mingw profile-build
```

fixes https://github.com/official-stockfish/Stockfish/issues/2769

closes https://github.com/official-stockfish/Stockfish/pull/2774

No functional change.
src/Makefile