fixes #21704; remove nfIsRef for genLit in VM (#21765)

* fixes #21704; remove `nfIsRef` for genLit

* remove nfIsRef from the output of macros

* make the logic better

* try again

* act together

* excl nfIsRef

(cherry picked from commit 53c15f24e9)

compiler/vmgen.nim

@@ -445,6 +445,7 @@ proc rawGenLiteral(c: PCtx; n: PNode): int =
   result = c.constants.len
   #assert(n.kind != nkCall)
   n.flags.incl nfAllConst
+  n.flags.excl nfIsRef
   c.constants.add n
   internalAssert c.config, result < regBxMax
 

tests/vm/t21704.nim

@@ -0,0 +1,69 @@
+discard """
+matrix: "--hints:off"
+nimout: '''
+Found 2 tests to run.
+Found 3 benches to compile.
+ 
+  --passC:-Wno-stringop-overflow --passL:-Wno-stringop-overflow 
+ 
+  --passC:-Wno-stringop-overflow --passL:-Wno-stringop-overflow 
+ 
+  --passC:-Wno-stringop-overflow --passL:-Wno-stringop-overflow
+'''
+"""
+# bug #21704
+import std/strformat
+
+const testDesc: seq[string] = @[
+  "tests/t_hash_sha256_vs_openssl.nim",
+  "tests/t_cipher_chacha20.nim"
+]
+const benchDesc = [
+  "bench_sha256",
+  "bench_hash_to_curve",
+  "bench_ethereum_bls_signatures"
+]
+
+proc setupTestCommand(flags, path: string): string =
+  return "nim c -r " &
+    flags &
+    &" --nimcache:nimcache/{path} " & # Commenting this out also solves the issue
+    path
+
+proc testBatch(commands: var string, flags, path: string) =
+  commands &= setupTestCommand(flags, path) & '\n'
+
+proc setupBench(benchName: string): string =
+  var runFlags = if false: " -r "
+                 else: " " # taking this branch is needed to trigger the bug
+
+  echo runFlags # Somehow runflags isn't reset in corner cases
+  runFlags &= " --passC:-Wno-stringop-overflow --passL:-Wno-stringop-overflow "
+  echo runFlags
+
+  return "nim c " &
+       runFlags &
+       &" benchmarks/{benchName}.nim"
+
+proc buildBenchBatch(commands: var string, benchName: string) =
+  let command = setupBench(benchName)
+  commands &= command & '\n'
+
+proc addTestSet(cmdFile: var string) =
+  echo "Found " & $testDesc.len & " tests to run."
+
+  for path in testDesc:
+    var flags = "" # This is important
+    cmdFile.testBatch(flags, path)
+
+proc addBenchSet(cmdFile: var string) =
+  echo "Found " & $benchDesc.len & " benches to compile."
+  for bd in benchDesc:
+    cmdFile.buildBenchBatch(bd)
+
+proc task_bug() =
+  var cmdFile: string
+  cmdFile.addTestSet() # Comment this out and there is no bug
+  cmdFile.addBenchSet()
+
+static: task_bug()