fixes some strictdefs warnings (#24502)

lib/system/alloc.nim

@@ -575,6 +575,7 @@ proc isAccessible(a: MemRegion, p: pointer): bool {.inline.} =
   result = contains(a.chunkStarts, pageIndex(p))
 
 proc contains[T](list, x: T): bool =
+  result = false
   var it = list
   while it != nil:
     if it == x: return true
@@ -1164,6 +1165,7 @@ proc dealloc(allocator: var MemRegion, p: pointer) =
     rawDealloc(allocator, p)
 
 proc realloc(allocator: var MemRegion, p: pointer, newsize: Natural): pointer =
+  result = nil
   if newsize > 0:
     result = alloc(allocator, newsize)
     if p != nil:

lib/system/arc.nim

@@ -211,6 +211,7 @@ when defined(gcOrc):
     #include cyclecollector
 
 proc nimDecRefIsLast(p: pointer): bool {.compilerRtl, inl.} =
+  result = false
   if p != nil:
     var cell = head(p)
 

lib/system/deepcopy.nim

@@ -41,6 +41,7 @@ proc initPtrTable(): PtrTable =
 template deinit(t: PtrTable) = dealloc(t)
 
 proc get(t: PtrTable; key: pointer): pointer =
+  result = nil
   var h = hashPtr(key)
   while true:
     let k = t.data[h and t.max][0]

lib/system/dollars.nim

@@ -11,24 +11,30 @@ when not defined(nimPreviewSlimSystem):
 
   func `$`*(x: float | float32): string =
     ## Outplace version of `addFloat`.
+    result = ""
     result.addFloat(x)
 
 proc `$`*(x: int): string {.raises: [].} =
   ## Outplace version of `addInt`.
+  result = ""
   result.addInt(x)
 
 proc `$`*(x: int64): string {.raises: [].} =
   ## Outplace version of `addInt`.
+  result = ""
   result.addInt(x)
 
 proc `$`*(x: uint64): string {.raises: [].} =
   ## Outplace version of `addInt`.
+  result = ""
   addInt(result, x)
 
 # same as old `ctfeWhitelist` behavior, whether or not this is a good idea.
 template gen(T) =
   # xxx simplify this by supporting this in compiler: int{lit} | uint64{lit} | int64{lit}
-  func `$`*(x: T{lit}): string {.compileTime.} = result.addInt(x)
+  func `$`*(x: T{lit}): string {.compileTime.} =
+    result = ""
+    result.addInt(x)
 gen(int)
 gen(uint64)
 gen(int64)

lib/system/integerops.nim

@@ -117,6 +117,7 @@ template divImplFallback(name, T) {.dirty.} =
     if a == low(T) and b == T(-1):
       result = true
     else:
+      result = false
       res[] = a div b
 
 divImplFallback(nimDivInt, int)

lib/system/memalloc.nim

@@ -85,7 +85,7 @@ when hasAlloc and not defined(js):
 
   else:
     template incStat(what: untyped) = discard
-    proc getAllocStats*(): AllocStats = discard
+    proc getAllocStats*(): AllocStats = result = default(AllocStats)
 
   template alloc*(size: Natural): pointer =
     ## Allocates a new memory block with at least `size` bytes.

lib/system/orc.nim

@@ -509,6 +509,7 @@ proc rememberCycle(isDestroyAction: bool; s: Cell; desc: PNimTypeV2) {.noinline.
       registerCycle(s, desc)
 
 proc nimDecRefIsLastCyclicDyn(p: pointer): bool {.compilerRtl, inl.} =
+  result = false
   if p != nil:
     var cell = head(p)
     if (cell.rc and not rcMask) == 0:
@@ -520,6 +521,7 @@ proc nimDecRefIsLastCyclicDyn(p: pointer): bool {.compilerRtl, inl.} =
     rememberCycle(result, cell, cast[ptr PNimTypeV2](p)[])
 
 proc nimDecRefIsLastDyn(p: pointer): bool {.compilerRtl, inl.} =
+  result = false
   if p != nil:
     var cell = head(p)
     if (cell.rc and not rcMask) == 0:
@@ -533,6 +535,7 @@ proc nimDecRefIsLastDyn(p: pointer): bool {.compilerRtl, inl.} =
         unregisterCycle(cell)
 
 proc nimDecRefIsLastCyclicStatic(p: pointer; desc: PNimTypeV2): bool {.compilerRtl, inl.} =
+  result = false
   if p != nil:
     var cell = head(p)
     if (cell.rc and not rcMask) == 0:

lib/system/strmantle.nim

@@ -32,6 +32,7 @@ proc ltStrings(a, b: string): bool {.inline, compilerproc.} =
   cmpStrings(a, b) < 0
 
 proc eqStrings(a, b: string): bool {.inline, compilerproc.} =
+  result = false
   let alen = a.len
   let blen = b.len
   if alen == blen:

lib/system/threadlocalstorage.nim

@@ -88,6 +88,7 @@ else:
     importc: "pthread_setspecific", header: pthreadh.}
 
   proc threadVarAlloc(): ThreadVarSlot {.inline.} =
+    result = default(ThreadVarSlot)
     discard pthread_key_create(addr(result), nil)
   proc threadVarSetValue(s: ThreadVarSlot, value: pointer) {.inline.} =
     discard pthread_setspecific(s, value)