Hi! After a year I wanted to build FS on windows and make video tutorial or for FS wiki. I am using latest VS2017 and everything builds except libpng project. Below is error if someone can help me, because I don't have c++ experience: 1>------ Build started: Project: Download zlib, Configuration: Release Win32 ------ 1>Downloading zlib. 2>------ Build started: Project: libpng, Configuration: Release x64 ------ 2>Generating pnglibconf.h 2> 1 file(s) copied. 2>png.c 2>pngerror.c 2>pngget.c 2>pngmem.c 2>pngpread.c 2>pngread.c 2>pngrio.c 2>pngrtran.c 2>pngrutil.c 2>pngset.c 2>pngtrans.c 2>pngwio.c 2>pngwrite.c 2>pngwtran.c 2>pngwutil.c 2>Generating Code... 2>zlib.lib(inflate.obj) : MSIL .netmodule or module compiled with /GL found; restarting link with /LTCG; add /LTCG to the link command line to improve linker performance 2> Creating library D:\Git\freeswitch\x64\Release\libpng16.lib and object D:\Git\freeswitch\x64\Release\libpng16.exp 2>Generating code 2>d:\git\freeswitch\libs\zlib\deflate.c(2097): error C2220: warning treated as error - no 'executable' file generated 2>d:\git\freeswitch\libs\zlib\deflate.c(2097): warning C5045: Compiler will insert Spectre mitigation for memory load if /Qspectre switch specified 2>d:\git\freeswitch\libs\zlib\deflate.c(2097) : note: index 'dist' range checked by comparison on this line 2>d:\git\freeswitch\libs\zlib\deflate.c(2097) : note: feeds memory load on this line 2>d:\git\freeswitch\libs\zlib\deflate.c(1987): warning C5045: Compiler will insert Spectre mitigation for memory load if /Qspectre switch specified 2>d:\git\freeswitch\libs\zlib\deflate.c(1987) : note: index 'dist' range checked by comparison on this line 2>d:\git\freeswitch\libs\zlib\deflate.c(1987) : note: feeds memory load on this line 2>d:\git\freeswitch\libs\zlib\deflate.c(1862): warning C5045: Compiler will insert Spectre mitigation for memory load if /Qspectre switch specified 2>d:\git\freeswitch\libs\zlib\deflate.c(1862) : note: index 'dist' range checked by comparison on this line 2>d:\git\freeswitch\libs\zlib\deflate.c(1862) : note: feeds memory load on this line 2>LINK : fatal error LNK1257: code generation failed 2>Done building project "libpng.vcxproj" -- FAILED. Best regards, Gregor