Passing generic parameter when T=void crashes compiler

[zielmicha]

proc bar[T](x: T): string =
  "something"

proc foo[T](x: T) =
  echo bar(x)

foo[void]()

->
Error: internal error: expr: param not init x_101019

This is somewhat related to #402 (feature request for better void handling).

[genotrance]

Stack trace.

Hint: used config file 'c:\users\gt\Desktop\DL\programming\nimdevel\config\nim.cfg' [Conf]
Hint: system [Processing]
Hint: temp [Processing]
temp.nim(7, 12) Error: internal error: expr: param not init x_110020
Traceback (most recent call last)
nim.nim(121)             nim
nim.nim(77)              handleCmdLine
main.nim(173)            mainCommand
main.nim(77)             commandCompileToC
modules.nim(242)         compileProject
modules.nim(182)         compileModule
passes.nim(250)          processModule
passes.nim(139)          processTopLevelStmt
cgen.nim(1375)           myProcess
ccgstmts.nim(1155)       genStmts
ccgexprs.nim(2210)       expr
ccgcalls.nim(549)        genCall
ccgcalls.nim(196)        genPrefixCall
cgen.nim(498)            initLocExpr
ccgexprs.nim(2149)       expr
cgen.nim(895)            genProc
cgen.nim(860)            genProcNoForward
cgen.nim(759)            genProcAux
ccgstmts.nim(1155)       genStmts
ccgexprs.nim(2208)       expr
ccgexprs.nim(1885)       genMagicExpr
ccgexprs.nim(994)        genEcho
cgen.nim(498)            initLocExpr
ccgexprs.nim(2228)       expr
ccgexprs.nim(2004)       genArrayConstr
ccgexprs.nim(2214)       expr
ccgexprs.nim(1840)       genMagicExpr
ccgexprs.nim(2216)       expr
ccgcalls.nim(549)        genCall
ccgcalls.nim(191)        genPrefixCall
ccgcalls.nim(179)        genArgNoParam
cgen.nim(503)            initLocExprSingleUse
ccgexprs.nim(2189)       expr
msgs.nim(1066)           internalError
msgs.nim(1037)           liMessage
msgs.nim(886)            handleError
msgs.nim(876)            quit