[cleanup] remove dead code compiler.options.mergeConfigs (#10165)

compiler/options.nim

@@ -253,84 +253,6 @@ template depConfigFields*(fn) {.dirty.} =
   fn(globalOptions)
   fn(selectedGC)
 
-proc mergeConfigs*(dest, src: ConfigRef; mergeSymbols: bool) =
-  template merge[T: enum](a, b: T) =
-    a = b
-  template merge[T](a, b: set[T]) =
-    a = a + b
-  template merge(a, b: int) =
-    inc a, b
-  template merge[T](a, b: seq[T]) =
-    for bb in b: a.add b
-  template merge(a, b: string) =
-    a = b
-  template merge[T: AbsoluteFile|AbsoluteDir](a, b: T) =
-    if a.isEmpty and not b.isEmpty: a = b
-
-  template merge[T](a, b: HashSet[T]) =
-    for bb in b: a.incl b
-  template merge(a, b: StringTableRef) =
-    for k, v in b: a[k] = v
-  template merge[T: object](a, b: T) =
-    a = b
-
-  template m(field) =
-    merge(dest.field, src.field)
-
-  m target
-  m options
-  m globalOptions
-  m cmd
-  m selectedGC
-  dest.verbosity = src.verbosity
-  m numberOfProcessors
-  m evalExpr
-  m symbolFiles
-  m cppDefines
-  m headerFile
-  m features
-  m arguments
-  m ideCmd
-  m cCompiler
-  m enableNotes
-  m disableNotes
-  m foreignPackageNotes
-  m notes
-  m errorCounter
-  m hintCounter
-  m warnCounter
-  m errorMax
-  m configVars
-  if mergeSymbols:
-    m symbols
-  m projectName
-  m projectPath
-  m projectFull
-  m searchPaths
-  m lazyPaths
-  m outFile
-  m prefixDir
-  m libpath
-  m nimcacheDir
-  m dllOverrides
-  m moduleOverrides
-  m command
-  m commandArgs
-  m implicitImports
-  m implicitIncludes
-  m docSeeSrcUrl
-  m cIncludes
-  m cLibs
-  m cLinkedLibs
-  m externalToLink
-  m linkOptionsCmd
-  m compileOptionsCmd
-  m linkOptions
-  m compileOptions
-  m ccompilerpath
-  m toCompile
-  m cppCustomNamespace
-
 const oldExperimentalFeatures* = {implicitDeref, dotOperators, callOperator, parallel}
 
 const