system.nim: refactoring that removes cyclic dependencies in prep for IC

lib/std/assertions.nim

@@ -19,12 +19,16 @@ import std/private/miscdollars
 
 type InstantiationInfo = tuple[filename: string, line: int, column: int]
 
+{.push overflowChecks: off, rangeChecks: off.}
+
 proc `$`(info: InstantiationInfo): string =
   # The +1 is needed here
   # instead of overriding `$` (and changing its meaning), consider explicit name.
   result = ""
   result.toLocation(info.filename, info.line, info.column + 1)
 
+{.pop.}
+
 # ---------------------------------------------------------------------------
 
 

lib/std/private/miscdollars.nim

@@ -4,7 +4,13 @@ template toLocation*(result: var string, file: string | cstring, line: int, col:
   ## avoids spurious allocations
   # Hopefully this can be re-used everywhere so that if a user needs to customize,
   # it can be done in a single place.
-  result.add file
+  when file is cstring:
+    var i = 0
+    while file[i] != '\0':
+      add(result, file[i])
+      inc i
+  else:
+    result.add file
   if line > 0:
     result.add "("
     addInt(result, line)