IC: bugfix (#17533)

* cleanups
* IC: bugfix

compiler/ic/ic.nim

@@ -28,6 +28,7 @@ type
 
   PackedModule* = object ## the parts of a PackedEncoder that are part of the .rod file
     definedSymbols: string
+    moduleFlags: TSymFlags
     includes: seq[(LitId, string)] # first entry is the module filename itself
     imports: seq[LitId] # the modules this module depends on
     toReplay: PackedTree # pragmas and VM specific state to replay.
@@ -139,6 +140,7 @@ proc initEncoder*(c: var PackedEncoder; m: var PackedModule; moduleSym: PSym; co
   m.sh = Shared()
   c.thisModule = moduleSym.itemId.module
   c.config = config
+  m.moduleFlags = moduleSym.flags
   m.bodies = newTreeFrom(m.topLevel)
   m.toReplay = newTreeFrom(m.topLevel)
 
@@ -511,6 +513,7 @@ proc loadRodFile*(filename: AbsoluteFile; m: var PackedModule; config: ConfigRef
   f.loadSection configSection
 
   f.loadPrim m.definedSymbols
+  f.loadPrim m.moduleFlags
   f.loadPrim m.cfg
 
   if f.err == ok and not configIdentical(m, config) and not ignoreConfig:
@@ -581,6 +584,7 @@ proc saveRodFile*(filename: AbsoluteFile; encoder: var PackedEncoder; m: var Pac
   f.storeHeader()
   f.storeSection configSection
   f.storePrim m.definedSymbols
+  f.storePrim m.moduleFlags
   f.storePrim m.cfg
 
   template storeSeqSection(section, data) {.dirty.} =
@@ -909,8 +913,7 @@ proc setupLookupTables(g: var PackedModuleGraph; conf: ConfigRef; cache: IdentCa
                   info: newLineInfo(fileIdx, 1, 1),
                   position: int(fileIdx))
   m.module.owner = newPackage(conf, cache, fileIdx)
-  if fileIdx == conf.projectMainIdx2:
-    m.module.flags.incl sfMainModule
+  m.module.flags = m.fromDisk.moduleFlags
 
 proc loadToReplayNodes(g: var PackedModuleGraph; conf: ConfigRef; cache: IdentCache;
                        fileIdx: FileIndex; m: var LoadedModule) =