Re: Unexec dumping results in "Segmentation fault" on Windows Msys2

[Nikolay Kudryavtsev]

This breaks 32 bit mingw64 build due to ld complaining:

D:/Emacs/msys64/mingw32/bin/../lib/gcc/i686-w64-mingw32/10.2.0/../../../../i686-w64-mingw32/bin/ld.exe: 
unrecognised option: -disable-high-entropy-va

So you also have to check whether we're doing a 64 bit build or not.

Also, while the Msys2 website is suggesting we use those particular 
forms, ld warns us:

D:/Emacs/msys64/mingw32/bin/../lib/gcc/i686-w64-mingw32/10.2.0/../../../../i686-w64-mingw32/bin/ld.exe: 
Warning: grouped short command line options are deprecated: 
-disable-high-entropy-va