Which sm or compiler are you use? I get a lot of erros with latest sm and all .inc files.
Original .sp for example.
//// Wallhack Round.sp
//
// H:\Downloads\Compressed\sourcemod-1.10.0-git6512-windows\addons\sourcemod\scripting\include\cs gocolors.inc(15) : warning 201: redefinition of constant/macro (symbol "MAX_MESSAGE_LENGTH")
// H:\Downloads\Compressed\sourcemod-1.10.0-git6512-windows\addons\sourcemod\scripting\include\cs gocolors.inc(109) : error 021: symbol already defined: "CSkipList"
// H:\Downloads\Compressed\sourcemod-1.10.0-git6512-windows\addons\sourcemod\scripting\include\cs gocolors.inc(127) : error 021: symbol already defined: "CPrintToChat"
// H:\Downloads\Compressed\sourcemod-1.10.0-git6512-windows\addons\sourcemod\scripting\include\cs gocolors.inc(127) : error 180: function return type differs from prototype. expected 'int', but got 'void'
// H:\Downloads\Compressed\sourcemod-1.10.0-git6512-windows\addons\sourcemod\scripting\include\cs gocolors.inc(162) : error 021: symbol already defined: "CReplyToCommand"
// H:\Downloads\Compressed\sourcemod-1.10.0-git6512-windows\addons\sourcemod\scripting\include\cs gocolors.inc(191) : error 021: symbol already defined: "CReplyToCommandEx"
// H:\Downloads\Compressed\sourcemod-1.10.0-git6512-windows\addons\sourcemod\scripting\include\cs gocolors.inc(215) : error 021: symbol already defined: "CPrintToChatAll"
// H:\Downloads\Compressed\sourcemod-1.10.0-git6512-windows\addons\sourcemod\scripting\include\cs gocolors.inc(215) : error 180: function return type differs from prototype. expected 'int', but got 'void'
// H:\Downloads\Compressed\sourcemod-1.10.0-git6512-windows\addons\sourcemod\scripting\include\cs gocolors.inc(244) : error 021: symbol already defined: "CPrintToChatEx"
// H:\Downloads\Compressed\sourcemod-1.10.0-git6512-windows\addons\sourcemod\scripting\include\cs gocolors.inc(281) : error 021: symbol already defined: "CPrintToChatAllEx"
// H:\Downloads\Compressed\sourcemod-1.10.0-git6512-windows\addons\sourcemod\scripting\include\cs gocolors.inc(312) : error 021: symbol already defined: "CRemoveTags"
// H:\Downloads\Compressed\sourcemod-1.10.0-git6512-windows\addons\sourcemod\scripting\include\cs gocolors.inc(355) : error 021: symbol already defined: "CSkipNextClient"
// H:\Downloads\Compressed\sourcemod-1.10.0-git6512-windows\addons\sourcemod\scripting\include\cs gocolors.inc(519) : error 021: symbol already defined: "CShowActivity"
// H:\Downloads\Compressed\sourcemod-1.10.0-git6512-windows\addons\sourcemod\scripting\include\cs gocolors.inc(631) : error 021: symbol already defined: "CShowActivityEx"
// H:\Downloads\Compressed\sourcemod-1.10.0-git6512-windows\addons\sourcemod\scripting\include\cs gocolors.inc(73
: error 021: symbol already defined: "CShowActivity2"
// H:\Downloads\Compressed\sourcemod-1.10.0-git6512-windows\addons\sourcemod\scripting\include\mu lticolors.inc(67) : error 021: symbol already defined: "CPrintToChat"
// H:\Downloads\Compressed\sourcemod-1.10.0-git6512-windows\addons\sourcemod\scripting\include\mu lticolors.inc(76) : error 017: undefined symbol "C_PrintToChat"
// H:\Downloads\Compressed\sourcemod-1.10.0-git6512-windows\addons\sourcemod\scripting\include\mu lticolors.inc(7
: error 017: undefined symbol "MC_PrintToChat"
// H:\Downloads\Compressed\sourcemod-1.10.0-git6512-windows\addons\sourcemod\scripting\include\mu lticolors.inc(67) : error 180: function return type differs from prototype. expected 'int', but got 'void'
// H:\Downloads\Compressed\sourcemod-1.10.0-git6512-windows\addons\sourcemod\scripting\include\mu lticolors.inc(90) : error 021: symbol already defined: "CPrintToChatAll"
// H:\Downloads\Compressed\sourcemod-1.10.0-git6512-windows\addons\sourcemod\scripting\include\mu lticolors.inc(99) : error 017: undefined symbol "C_PrintToChatAll"
// H:\Downloads\Compressed\sourcemod-1.10.0-git6512-windows\addons\sourcemod\scripting\include\mu lticolors.inc(101) : error 017: undefined symbol "MC_PrintToChatAll"
// H:\Downloads\Compressed\sourcemod-1.10.0-git6512-windows\addons\sourcemod\scripting\include\mu lticolors.inc(90) : error 180: function return type differs from prototype. expected 'int', but got 'void'
// H:\Downloads\Compressed\sourcemod-1.10.0-git6512-windows\addons\sourcemod\scripting\include\mu lticolors.inc(143) : error 021: symbol already defined: "CPrintToChatEx"
// H:\Downloads\Compressed\sourcemod-1.10.0-git6512-windows\addons\sourcemod\scripting\include\mu lticolors.inc(163) : error 021: symbol already defined: "CPrintToChatAllEx"
// H:\Downloads\Compressed\sourcemod-1.10.0-git6512-windows\addons\sourcemod\scripting\include\mu lticolors.inc(214) : error 021: symbol already defined: "CReplyToCommand"
// H:\Downloads\Compressed\sourcemod-1.10.0-git6512-windows\addons\sourcemod\scripting\include\mu lticolors.inc(237) : error 021: symbol already defined: "CReplyToCommandEx"
//
// Compilation aborted.
// 26 Errors.
//
// Compilation Time: 0,17 sec