fixes #5479

compiler/cgmeth.nim

@@ -73,7 +73,7 @@ proc sameMethodBucket(a, b: PSym): MethodResult =
         bb = bb.lastSon
       else:
         break
-    if sameType(aa, bb):
+    if sameType(a.typ.sons[i], b.typ.sons[i]):
       if aa.kind == tyObject and result != Invalid:
         result = Yes
     elif aa.kind == tyObject and bb.kind == tyObject:
@@ -83,7 +83,7 @@ proc sameMethodBucket(a, b: PSym): MethodResult =
           result = Yes
         else:
           return No
-      elif diff != high(int):
+      elif diff != high(int) and sfFromGeneric notin (a.flags+b.flags):
         result = Invalid
       else:
         return No

compiler/semtypinst.nim

@@ -373,12 +373,17 @@ proc handleGenericInvocation(cl: var TReplTypeVars, t: PType): PType =
         else:
           newbody.lastSon.typeInst = result
     cl.c.typesWithOps.add((newbody, result))
-    let methods = skipTypes(bbody, abstractPtrs).methods
-    for col, meth in items(methods):
-      # we instantiate the known methods belonging to that type, this causes
-      # them to be registered and that's enough, so we 'discard' the result.
-      discard cl.c.instTypeBoundOp(cl.c, meth, result, cl.info,
-        attachedAsgn, col)
+    let mm = skipTypes(bbody, abstractPtrs)
+    if tfFromGeneric notin mm.flags:
+      # bug #5479, prevent endless recursions here:
+      incl mm.flags, tfFromGeneric
+      let methods = mm.methods
+      for col, meth in items(methods):
+        # we instantiate the known methods belonging to that type, this causes
+        # them to be registered and that's enough, so we 'discard' the result.
+        discard cl.c.instTypeBoundOp(cl.c, meth, result, cl.info,
+          attachedAsgn, col)
+      excl mm.flags, tfFromGeneric
 
 proc eraseVoidParams*(t: PType) =
   # transform '(): void' into '()' because old parts of the compiler really

tests/method/tgeneric_methods.nim

@@ -1,5 +1,7 @@
 discard """
-  output: "wow2"
+  output: '''wow2
+X 1
+X 3'''
 """
 type
   First[T] = ref object of RootObj
@@ -22,3 +24,18 @@ proc takeFirst(x: First[int]) =
   wow(2, x)
 
 takeFirst(x)
+
+
+# bug #5479
+type
+  Base[T: static[int]] = ref object of RootObj
+
+method test[T](t: Base[T]) {.base.} =
+  echo "X ", t.T
+
+let ab = Base[1]()
+
+ab.test()
+
+let ac = Base[3]()
+ac.test()