fixes #1055

compiler/ast.nim

@@ -1055,7 +1055,7 @@ proc discardSons(father: PNode) =
   father.sons = nil
 
 when defined(useNodeIds):
-  const nodeIdToDebug* = 310841 # 612794
+  const nodeIdToDebug* = -1 # 884953 # 612794
   #612840 # 612905 # 614635 # 614637 # 614641
   # 423408
   #429107 # 430443 # 441048 # 441090 # 441153

compiler/seminst.nim

@@ -157,8 +157,7 @@ proc instantiateProcType(c: PContext, pt: TIdTable,
   #   
   # The solution would be to move this logic into semtypinst, but
   # at this point semtypinst have to become part of sem, because it
-  # will need to use openScope, addDecl, etc
-  #
+  # will need to use openScope, addDecl, etc.
   addDecl(c, prc)
   
   pushInfoContext(info)
@@ -223,7 +222,11 @@ proc generateInstance(c: PContext, fn: PSym, pt: TIdTable,
   n.sons[genericParamsPos] = ast.emptyNode
   var oldPrc = genericCacheGet(fn, entry[])
   if oldPrc == nil:
-    fn.procInstCache.safeAdd(entry)
+    # we MUST not add potentially wrong instantiations to the caching mechanism.
+    # This means recursive instantiations behave differently when in
+    # a ``compiles`` context but this is the lesser evil. See
+    # bug #1055 (tevilcompiles).
+    if c.inCompilesContext == 0: fn.procInstCache.safeAdd(entry)
     c.generics.add(makeInstPair(fn, entry))
     if n.sons[pragmasPos].kind != nkEmpty:
       pragma(c, result, n.sons[pragmasPos], allRoutinePragmas)

doc/intern.txt

@@ -118,6 +118,34 @@ Thus we need to serialize this graph as RTTI for C code generation.
 Look at the file ``lib/system/hti.nim`` for more information.
 
 
+Debugging the compiler
+======================
+
+You can of course use GDB or Visual Studio to debug the 
+compiler (via ``--debuginfo --lineDir:on``). However, there
+are also lots of procs that aid in debugging:
+
+
+.. code-block:: nim
+  # pretty prints the Nim AST
+  echo renderTree(someNode)
+  # outputs some JSON representation
+  debug(someNode)
+  # pretty prints some type
+  echo typeToString(someType)
+  debug(someType)
+  echo symbol.name.s
+  debug(symbol)
+  # pretty prints the nimrod ast, but annotates symbol IDs:
+  echo renderTree(someNode, {renderIds})
+  if n.info ?? "temp.nim":
+    # only output when it comes from "temp.nim"
+    echo renderTree(n)
+  if n.info ?? "temp.nim":
+    # why does it process temp.nim here?
+    writeStackTrace()
+
+
 The compiler's architecture
 ===========================
 
@@ -255,16 +283,14 @@ turned on".
 
 
 Debugging Nim's memory management
-====================================
+=================================
 
 The following paragraphs are mostly a reminder for myself. Things to keep
 in mind:
 
-* Segmentation faults can have multiple reasons: One that is frequently
-  forgotten is that *stack overflow* can trigger one!
 * If an assertion in Nim's memory manager or GC fails, the stack trace
   keeps allocating memory! Thus a stack overflow may happen, hiding the
-  real issue. 
+  real issue.
 * What seem to be C code generation problems is often a bug resulting from
   not producing prototypes, so that some types default to ``cint``. Testing
   without the ``-w`` option helps!
@@ -304,8 +330,8 @@ modifying a ``TCellSet`` during traversation leads to undefined behaviour.
   type
     TCellSet # hidden
 
-  proc CellSetInit(s: var TCellSet) # initialize a new set
-  proc CellSetDeinit(s: var TCellSet) # empty the set and free its memory
+  proc cellSetInit(s: var TCellSet) # initialize a new set
+  proc cellSetDeinit(s: var TCellSet) # empty the set and free its memory
   proc incl(s: var TCellSet, elem: PCell) # include an element
   proc excl(s: var TCellSet, elem: PCell) # exclude an element
 
@@ -493,7 +519,7 @@ Accumulator
 -----------
 
 .. code-block:: nim
-  proc GetAccumulator(start: int): proc (): int {.closure} = 
+  proc getAccumulator(start: int): proc (): int {.closure} = 
     var i = start
     return lambda: int = 
       inc i

lib/packages/docutils/rstgen.nim

@@ -728,9 +728,9 @@ proc renderTocEntry(d: PDoc, e: TTocEntry, result: var string) =
     "\\item\\label{$1_toc} $2\\ref{$1}\n", [e.refname, e.header])
 
 proc renderTocEntries*(d: var TRstGenerator, j: var int, lvl: int,
-    result: var string) =
+                       result: var string) =
   var tmp = ""
-  while j <= high(d.tocPart): 
+  while j <= high(d.tocPart):
     var a = abs(d.tocPart[j].n.level)
     if a == lvl:
       renderTocEntry(d, d.tocPart[j], tmp)
@@ -740,11 +740,11 @@ proc renderTocEntries*(d: var TRstGenerator, j: var int, lvl: int,
     else:
       break
   if lvl > 1:
-    dispA(d.target, result, "<ul class=\"simple\">$1</ul>", 
+    dispA(d.target, result, "<ul class=\"simple\">$1</ul>",
                             "\\begin{enumerate}$1\\end{enumerate}", [tmp])
   else:
     result.add(tmp)
-  
+
 proc renderImage(d: PDoc, n: PRstNode, result: var string) = 
   var options = ""
   var s = getFieldValue(n, "scale")

tests/compiles/tevilcompiles.nim

@@ -0,0 +1,12 @@
+# bug #1055
+import unittest
+type TMatrix*[N,M: static[int], T] = object
+  data*: array[0..N*M-1, T]
+proc `==`*(a: distinct TMatrix; b: distinct TMatrix): bool =
+  result = a.data == b.data
+
+test "c":
+  var a = TMatrix[2,2,int](data: [1,2,3,4])
+  var b = TMatrix[2,2,int](data: [1,2,3,4])
+  check(a == b)
+