workaround windows SIGSEGV stdlib_winleanDatInit000

Author: timotheecour

compiler/cgen.nim

@@ -697,11 +697,14 @@ proc loadDynamicLib(m: BModule, lib: PLib) =
 proc mangleDynLibProc(sym: PSym): Rope =
   # we have to build this as a single rope in order not to trip the
   # optimization in genInfixCall, see test tests/cpp/t8241.nim
-  if sym.loc.r != nil:
-    if sym.loc.r.data.len > 0:
-      return sym.loc.r
-    else:
-      return rope($sym.loc.r)
+  when not defined(windows):
+    # mysterious bug that only affects windows, causing SIGSEGV in
+    # stdlib_winleanDatInit000 () at generated_not_to_break_here
+    if sym.loc.r != nil:
+      if sym.loc.r.data.len > 0:
+        return sym.loc.r
+      else:
+        return rope($sym.loc.r)
   if sfCompilerProc in sym.flags:
     # NOTE: sym.loc.r is the external name!
     result = rope(sym.name.s)