distinguish between 'defined' and 'declared'

compiler/commands.nim

@@ -315,6 +315,9 @@ proc processSwitch(switch, arg: string, pass: TCmdLinePass, info: TLineInfo) =
   of "undef", "u": 
     expectArg(switch, arg, pass, info)
     undefSymbol(arg)
+  of "symbol":
+    expectArg(switch, arg, pass, info)
+    declareSymbol(arg)  
   of "compile": 
     expectArg(switch, arg, pass, info)
     if pass in {passCmd2, passPP}: processCompile(arg)

compiler/condsyms.nim

@@ -19,6 +19,9 @@ var gSymbols: PStringTable
 proc defineSymbol*(symbol: string) = 
   gSymbols[symbol] = "true"
 
+proc declareSymbol*(symbol: string) = 
+  gSymbols[symbol] = "unknown"
+
 proc undefSymbol*(symbol: string) = 
   gSymbols[symbol] = "false"
 
@@ -27,6 +30,7 @@ proc isDefined*(symbol: string): bool =
     result = gSymbols[symbol] == "true"
   
 proc isDefined*(symbol: PIdent): bool = isDefined(symbol.s)
+proc isDeclared*(symbol: PIdent): bool = gSymbols.hasKey(symbol.s)
 
 iterator definedSymbolNames*: string =
   for key, val in pairs(gSymbols):
@@ -37,6 +41,36 @@ proc countDefinedSymbols*(): int =
   for key, val in pairs(gSymbols):
     if val == "true": inc(result)
 
+# For ease of bootstrapping, we keep there here and not in the global config
+# file for now:
+const
+  additionalSymbols = """
+    x86 itanium x8664
+    msdos mswindows win32 unix posix sunos bsd macintosh RISCOS doslike hpux
+    mac
+
+    hppa hp9000 hp9000s300 hp9000s700 hp9000s800 hp9000s820 ELATE sparcv9
+
+    ecmascript js nimrodvm nimffi nimdoc cpp objc
+    gcc llvmgcc clang lcc bcc dmc wcc vcc tcc pcc ucc icl
+    boehmgc gcmarkandsweep gcgenerational nogc gcUseBitvectors
+    endb profiler
+    executable guiapp consoleapp library dll staticlib
+
+    quick nimbabel
+    release debug
+    useWinAnsi useFork useNimRtl useMalloc useRealtimeGC ssl memProfiler
+    nodejs kwin
+
+    usesysassert usegcassert tinyC useFFI
+    useStdoutAsStdmsg createNimRtl
+    booting fulldebug corruption nimsuperops noSignalHandler useGnuReadline
+    noCaas noDocGen noBusyWaiting nativeStackTrace useNodeIds selftest
+    reportMissedDeadlines avoidTimeMachine useClone ignoreAllocationSize
+    debugExecProcesses pcreDll useLipzipSrc
+    preventDeadlocks UNICODE winUnicode trackGcHeaders posixRealtime
+  """.split
+
 proc initDefines*() = 
   gSymbols = newStringTable(modeStyleInsensitive)
   defineSymbol("nimrod") # 'nimrod' is always defined
@@ -53,6 +87,17 @@ proc initDefines*() =
   defineSymbol("nimparsebiggestfloatmagic")
   
   # add platform specific symbols:
+  for c in low(CPU)..high(CPU):
+    declareSymbol("cpu" & $CPU[c].bit)
+    declareSymbol(normalize(EndianToStr[CPU[c].endian]))
+    declareSymbol(CPU[c].name)
+  for o in low(platform.OS)..high(platform.OS):
+    declareSymbol(platform.OS[o].name)
+
+  for a in additionalSymbols:
+    declareSymbol(a)
+
+  # -----------------------------------------------------------
   case targetCPU
   of cpuI386: defineSymbol("x86")
   of cpuIa64: defineSymbol("itanium")
@@ -88,5 +133,6 @@ proc initDefines*() =
   defineSymbol(normalize(EndianToStr[CPU[targetCPU].endian]))
   defineSymbol(CPU[targetCPU].name)
   defineSymbol(platform.OS[targetOS].name)
+  declareSymbol("emulatedthreadvars")
   if platform.OS[targetOS].props.contains(ospLacksThreadVars):
     defineSymbol("emulatedthreadvars")

compiler/llstream.nim

@@ -77,7 +77,7 @@ proc llStreamClose(s: PLLStream) =
   of llsFile: 
     close(s.f)
 
-when not defined(readLineFromStdin): 
+when not declared(readLineFromStdin): 
   # fallback implementation:
   proc readLineFromStdin(prompt: string, line: var string): bool =
     stdout.write(prompt)

compiler/nimrod.nim

@@ -79,7 +79,7 @@ proc handleCmdLine() =
           var ex = quoteShell(binPath)
           execExternalProgram(ex & ' ' & service.arguments)
 
-when defined(GC_setMaxPause):
+when declared(GC_setMaxPause):
   GC_setMaxPause 2_000
 
 when compileOption("gc", "v2") or compileOption("gc", "refc"):

compiler/semexprs.nim

@@ -1393,10 +1393,16 @@ proc semDefined(c: PContext, n: PNode, onlyCurrentScope: bool): PNode =
   checkSonsLen(n, 2)
   # we replace this node by a 'true' or 'false' node:
   result = newIntNode(nkIntLit, 0)
-  if lookUpForDefined(c, n.sons[1], onlyCurrentScope) != nil: 
-    result.intVal = 1
-  elif not onlyCurrentScope and (n.sons[1].kind == nkIdent) and
-      condsyms.isDefined(n.sons[1].ident): 
+  if not onlyCurrentScope and considerQuotedIdent(n[0]).s == "defined":
+    if n.sons[1].kind != nkIdent:
+      localError(n.info, "obsolete usage of 'defined', use 'declared' instead")
+    elif condsyms.isDefined(n.sons[1].ident):
+      result.intVal = 1
+    elif not condsyms.isDeclared(n.sons[1].ident):
+      message(n.info, warnUser,
+        "undeclared conditional symbol; use --symbol to declare it: " &
+        n[1].ident.s)
+  elif lookUpForDefined(c, n.sons[1], onlyCurrentScope) != nil: 
     result.intVal = 1
   result.info = n.info
   result.typ = getSysType(tyBool)

compiler/testability.nim

@@ -1,5 +1,5 @@
 template tests*(body: stmt) {.immediate.} =
   when defined(selftest):
-    when not defined(unittest): import unittest
+    when not declared(unittest): import unittest
     body
 

compiler/vm.nim

@@ -87,9 +87,7 @@ proc bailOut(c: PCtx; tos: PStackFrame) =
 when not defined(nimComputedGoto):
   {.pragma: computedGoto.}
 
-proc myreset(n: var TFullReg) =
-  when defined(system.reset): 
-    reset(n)
+proc myreset(n: var TFullReg) = reset(n)
 
 template ensureKind(k: expr) {.immediate, dirty.} =
   if regs[ra].kind != k: