Nintendo switch support (#8069)

* Add config section for Nintendo Switch
* Add compiler configuration for Nintendo Switch and it's CPU
* Add specific lib code for Nintendo Switch
* Add GC support for Nintendo Switch
* Update changelog for Nintendo Switch
* Update changelog with more info about fixed paths
* Cleaned up GC memory management a bit
* Relocate docs for Switch
* Rename aarch64NoneElfGcc to nintendoSwitchGCC
* Remove armv8a57
* Fix installer.ini
* Reuse code in linux and amd64
* Add posix defs for nintendo switch
* Add more defined sections for nintendo switch
* Remove old comment
* Add what's not supported for Nintendo Switch docs
* Make nintendoswitch == posix
* Remove DEVKITPRO references from nim.cfg
* Make PR extccomp changes
* Remove Result type alias
* Add separate switch consts file
* Update docs for nintendo switch
* Fix travis errors with undefined consts and add correct wait.h procs

lib/pure/dynlib.nim

@@ -137,6 +137,28 @@ when defined(posix):
   proc symAddr(lib: LibHandle, name: cstring): pointer =
     return dlsym(lib, name)
 
+elif defined(nintendoswitch):
+  #
+  # =========================================================================
+  # Nintendo switch DevkitPro sdk does not have these. Raise an error if called.
+  # =========================================================================
+  #
+
+  proc dlclose(lib: LibHandle) =
+    raise newException(OSError, "dlclose not implemented on Nintendo Switch!")
+  proc dlopen(path: cstring, mode: int): LibHandle =
+    raise newException(OSError, "dlopen not implemented on Nintendo Switch!")
+  proc dlsym(lib: LibHandle, name: cstring): pointer =
+    raise newException(OSError, "dlsym not implemented on Nintendo Switch!")
+  proc loadLib(path: string, global_symbols=false): LibHandle =
+    raise newException(OSError, "loadLib not implemented on Nintendo Switch!")
+  proc loadLib(): LibHandle =
+    raise newException(OSError, "loadLib not implemented on Nintendo Switch!")
+  proc unloadLib(lib: LibHandle) =
+    raise newException(OSError, "unloadLib not implemented on Nintendo Switch!")
+  proc symAddr(lib: LibHandle, name: cstring): pointer =
+    raise newException(OSError, "symAddr not implemented on Nintendo Switch!")
+
 elif defined(windows) or defined(dos):
   #
   # =======================================================================

lib/pure/os.nim

@@ -819,7 +819,8 @@ iterator walkDir*(dir: string; relative=false): tuple[kind: PathComponent, path:
               y = dir / y
             var k = pcFile
 
-            when defined(linux) or defined(macosx) or defined(bsd) or defined(genode):
+            when defined(linux) or defined(macosx) or
+                 defined(bsd) or defined(genode) or defined(nintendoswitch):
               if x.d_type != DT_UNKNOWN:
                 if x.d_type == DT_DIR: k = pcDir
                 if x.d_type == DT_LNK:
@@ -1283,6 +1284,13 @@ elif defined(windows):
     if i < ownArgv.len and i >= 0: return TaintedString(ownArgv[i])
     raise newException(IndexError, "invalid index")
 
+elif defined(nintendoswitch):
+  proc paramStr*(i: int): TaintedString {.tags: [ReadIOEffect].} =
+    raise newException(OSError, "paramStr is not implemented on Nintendo Switch")
+
+  proc paramCount*(): int {.tags: [ReadIOEffect].} =
+    raise newException(OSError, "paramCount is not implemented on Nintendo Switch")
+
 elif not defined(createNimRtl) and
   not(defined(posix) and appType == "lib") and
   not defined(genode):
@@ -1439,7 +1447,7 @@ proc getAppFilename*(): string {.rtl, extern: "nos$1", tags: [ReadIOEffect].} =
       result = getApplAux("/proc/self/exe")
     elif defined(solaris):
       result = getApplAux("/proc/" & $getpid() & "/path/a.out")
-    elif defined(genode):
+    elif defined(genode) or defined(nintendoswitch):
       raiseOSError(OSErrorCode(-1), "POSIX command line not supported")
     elif defined(freebsd) or defined(dragonfly):
       result = getApplFreebsd()

lib/pure/ospaths.nim

@@ -597,7 +597,7 @@ proc quoteShellPosix*(s: string): string {.noSideEffect, rtl, extern: "nosp$1".}
   else:
     return "'" & s.replace("'", "'\"'\"'") & "'"
 
-when defined(windows) or defined(posix):
+when defined(windows) or defined(posix) or defined(nintendoswitch):
   proc quoteShell*(s: string): string {.noSideEffect, rtl, extern: "nosp$1".} =
     ## Quote ``s``, so it can be safely passed to shell.
     when defined(windows):

lib/pure/selectors.nim

@@ -312,6 +312,8 @@ else:
     include ioselects/ioselectors_poll # need to replace it with event ports
   elif defined(genode):
     include ioselects/ioselectors_select # TODO: use the native VFS layer
+  elif defined(nintendoswitch):
+    include ioselects/ioselectors_select
   else:
     include ioselects/ioselectors_poll