diff --git a/docs/lang/preprocessor.md b/docs/lang/preprocessor.md
index d7cbfc3d..1bacdd62 100644
--- a/docs/lang/preprocessor.md
+++ b/docs/lang/preprocessor.md
@@ -30,19 +30,35 @@ You can also define feature values using the `-D` command line option.
 
 ### Built-in features
 
+The following features are defined based on the chosen CPU and compilation options:
+
 * `ARCH_6502` – 1 if compiling for 6502, 0 otherwise
 
-* `CPUFEATURE_65C02` – 1 if compiling for 65C02-compatible processor, 0 otherwise
-
-* `CPUFEATURE_65CE02` – 1 if compiling for 65CE02-compatible processor, 0 otherwise
-
 * `ARCH_I80` – 1 if compiling for Intel 8080-like processor, 0 otherwise
 
-* `CPUFEATURE_8080` – 1 if compiling for Intel 8080-compatible processor, 0 otherwise
+* `CPU_65C02`, `CPU_65CE02`, `CPU_65816`, `CPU_HUC6280`, `CPU_8080`, `CPU_GAMEBOY`, `CPU_Z80`
+– 1 if compiling for the exact given processor, 0 otherwise
 
-* `CPUFEATURE_GAMEBOY` – 1 if compiling for Sharp LR35902-compatible processor, 0 otherwise
+* `CPU_6502` – 1 if compiling for any pre-65C02 6502-like processor, 0 otherwise
 
-* `CPUFEATURE_Z80` – 1 if compiling for Z80-compatible processor, 0 otherwise
+* `CPUFEATURE_DECIMAL_MODE` – 1 if decimal mode is enabled, 0 otherwise
+
+* `CPUFEATURE_65C02`, `CPUFEATURE_65CE02`, `CPUFEATURE_HUC6280`, `CPUFEATURE_65816_EMULATION`, `CPUFEATURE_65816_NATIVE`,
+`CPUFEATURE_8080`, `CPUFEATURE_GAMEBOY`, `CPUFEATURE_Z80`,
+`CPUFEATURE_6502_ILLEGALS`, `CPUFEATURE_Z80_ILLEGALS` – 1 if given instruction subset is enabled, 0 otherwise
+
+* `OPTIMIZE_FOR_SIZE`, `OPTIMIZE_FOR_SPEED`, `OPTIMIZE_INLINE`, `OPTIMIZE_IPO`
+– 1 if given optimization setting is enabled, 0 otherwise
+
+* `SYNTAX_INTEL`, `SYNTAX_ZILOG` – 1 if given assembly syntax is chosen, 0 otherwise; doesn't take this file's pragmas into account
+
+* `USES_ZPREG` – 1 if the zeropage pseudoregister is used, 0 otherwise
+
+* `ZPREG_SIZE` – size of the pseudoregister in bytes
+
+* `USES_IX_STACK`, `USES_IY_STACK` – 1 if given index register is used as a base pointer for stack-allocated variables, 0 otherwise 
+
+* `USES_SHADOW_REGISTERS` – 1 if interrupts preserve old registers in the shadow registers, 0 otherwise
 
 ### Commonly used features
 
@@ -52,12 +68,18 @@ You can also define feature values using the `-D` command line option.
 
 * `CBM_64` – 1 if the target is an 8-bit Commodore computer compatible with Commodore 64, 0 otherwise
 
+* `CBM_264` – 1 if the target is an 8-bit Commodore computer from the 264 line, 0 otherwise
+
 * `KEYBOARD` – 1 if the target has a keyboard, 0 otherwise
 
 * `JOYSTICKS` – the maximum number of joysticks using standard hardware configurations, may be 0
 
 * `HAS_BITMAP_MODE` – 1 if the target has a display mode with every pixel addressable, 0 otherwise
 
+* `MOS_6510` – 1 if the target uses a MOS 6510-compatible processor (with an I/O port at $0000/$0001)
+
+* `CPM` – 1 if the target is CP/M, 0 otherwise
+
 ### Built-in preprocessor functions and operators
 
 The `defined` function returns 1 if the feature is defined, 0 otherwise.  
diff --git a/src/main/scala/millfork/CompilationOptions.scala b/src/main/scala/millfork/CompilationOptions.scala
index 9c384ad2..71e92777 100644
--- a/src/main/scala/millfork/CompilationOptions.scala
+++ b/src/main/scala/millfork/CompilationOptions.scala
@@ -10,6 +10,7 @@ case class CompilationOptions(platform: Platform,
                               commandLineFlags: Map[CompilationFlag.Value, Boolean],
                               outputFileName: Option[String],
                               zpRegisterSize: Int,
+                              featureOverrides: Map[String, Long],
                               jobContext: JobContext) {
 
   import CompilationFlag._
@@ -162,6 +163,38 @@ case class CompilationOptions(platform: Platform,
         }
     }
   }
+
+  def features: Map[String, Long] = {
+    @inline
+    def toLong(b: Boolean): Long = if (b) 1L else 0L
+    val featuresFromOptions = Map[String, Long](
+      "OPTIMIZE_FOR_SIZE" -> toLong(flag(CompilationFlag.OptimizeForSize)),
+      "OPTIMIZE_FOR_SPEED" -> toLong(flag(CompilationFlag.OptimizeForSpeed)),
+      "OPTIMIZE_INLINE" -> toLong(flag(CompilationFlag.InlineFunctions)),
+      "OPTIMIZE_IPO" -> toLong(flag(CompilationFlag.InterproceduralOptimization)),
+      "CPUFEATURE_DECIMAL_MODE" -> toLong(flag(CompilationFlag.DecimalMode)),
+      "CPUFEATURE_Z80" -> toLong(flag(CompilationFlag.EmitZ80Opcodes)),
+      "CPUFEATURE_EZ80" -> toLong(flag(CompilationFlag.EmitEZ80Opcodes)),
+      "CPUFEATURE_8080" -> toLong(flag(CompilationFlag.EmitIntel8080Opcodes)),
+      "CPUFEATURE_GAMEBOY" -> toLong(flag(CompilationFlag.EmitSharpOpcodes)),
+      "CPUFEATURE_65C02" -> toLong(flag(CompilationFlag.EmitCmosOpcodes)),
+      "CPUFEATURE_65CE02" -> toLong(flag(CompilationFlag.Emit65CE02Opcodes)),
+      "CPUFEATURE_HUC6280" -> toLong(flag(CompilationFlag.EmitHudsonOpcodes)),
+      "CPUFEATURE_65816_EMULATION" -> toLong(flag(CompilationFlag.EmitEmulation65816Opcodes)),
+      "CPUFEATURE_65816_NATIVE" -> toLong(flag(CompilationFlag.EmitNative65816Opcodes)),
+      "CPUFEATURE_6502_ILLEGALS" -> toLong(platform.cpuFamily == CpuFamily.M6502 && flag(CompilationFlag.EmitIllegals)),
+      "CPUFEATURE_Z80_ILLEGALS" -> toLong(platform.cpuFamily == CpuFamily.I80 && flag(CompilationFlag.EmitIllegals)),
+      "SYNTAX_INTEL" -> toLong(platform.cpuFamily == CpuFamily.I80 && flag(CompilationFlag.UseIntelSyntaxForInput)),
+      "SYNTAX_ZILOG" -> toLong(platform.cpuFamily == CpuFamily.I80 && !flag(CompilationFlag.UseIntelSyntaxForInput)),
+      "USES_ZPREG" -> toLong(platform.cpuFamily == CpuFamily.M6502 && zpRegisterSize > 0),
+      "USES_IX_STACK" -> toLong(flag(CompilationFlag.UseIxForStack)),
+      "USES_IY_STACK" -> toLong(flag(CompilationFlag.UseIyForStack)),
+      "USES_SHADOW_REGISTERS" -> toLong(flag(CompilationFlag.UseShadowRegistersForInterrupts)),
+      "ZPREG_SIZE" -> (if (platform.cpuFamily == CpuFamily.M6502) zpRegisterSize.toLong else 0)
+    )
+    platform.features ++ featuresFromOptions ++ featureOverrides
+  }
+
 }
 
 object CpuFamily extends Enumeration {
diff --git a/src/main/scala/millfork/Main.scala b/src/main/scala/millfork/Main.scala
index ca26feed..620c578c 100644
--- a/src/main/scala/millfork/Main.scala
+++ b/src/main/scala/millfork/Main.scala
@@ -80,8 +80,8 @@ object Main {
     val platform = Platform.lookupPlatformFile(c.includePath, c.platform.getOrElse {
       errorReporting.info("No platform selected, defaulting to `c64`")
       "c64"
-    }, c.features)
-    val options = CompilationOptions(platform, c.flags, c.outputFileName, c.zpRegisterSize.getOrElse(platform.zpRegisterSize), JobContext(errorReporting, new LabelGenerator))
+    })
+    val options = CompilationOptions(platform, c.flags, c.outputFileName, c.zpRegisterSize.getOrElse(platform.zpRegisterSize), c.features, JobContext(errorReporting, new LabelGenerator))
     errorReporting.debug("Effective flags: ")
     options.flags.toSeq.sortBy(_._1).foreach{
       case (f, b) => errorReporting.debug(f"    $f%-30s : $b%s")
diff --git a/src/main/scala/millfork/Platform.scala b/src/main/scala/millfork/Platform.scala
index 3e018fc1..234f24e8 100644
--- a/src/main/scala/millfork/Platform.scala
+++ b/src/main/scala/millfork/Platform.scala
@@ -42,18 +42,18 @@ class Platform(
 
 object Platform {
 
-  def lookupPlatformFile(includePath: List[String], platformName: String, featureOverrides: Map[String, Long])(implicit log: Logger): Platform = {
+  def lookupPlatformFile(includePath: List[String], platformName: String)(implicit log: Logger): Platform = {
     includePath.foreach { dir =>
       val file = Paths.get(dir, platformName + ".ini").toFile
       log.debug("Checking " + file)
       if (file.exists()) {
-        return load(file, featureOverrides)
+        return load(file)
       }
     }
     log.fatal(s"Platfom definition `$platformName` not found", None)
   }
 
-  def load(file: File, featureOverrides: Map[String, Long])(implicit log: Logger): Platform = {
+  def load(file: File)(implicit log: Logger): Platform = {
     val conf = new INIConfiguration()
     val bytes = Files.readAllBytes(file.toPath)
     conf.read(new StringReader(new String(bytes, StandardCharsets.UTF_8)))
@@ -219,7 +219,7 @@ object Platform {
       startingModules,
       codec,
       srcCodec,
-      builtInFeatures ++ definedFeatures ++ featureOverrides,
+      builtInFeatures ++ definedFeatures,
       outputPackager,
       codeAllocators.toMap,
       variableAllocators.toMap,
@@ -232,29 +232,25 @@ object Platform {
       outputStyle)
   }
 
-  @inline
-  private def toLong(b: Boolean): Long = if (b) 1L else 0L
-
   def builtInCpuFeatures(cpu: Cpu.Value): Map[String, Long] = {
+    @inline
+    def toLong(b: Boolean): Long = if (b) 1L else 0L
     Map[String, Long](
       "ARCH_6502" -> toLong(CpuFamily.forType(cpu) == CpuFamily.M6502),
-      "CPUFEATURE_65C02" -> toLong(Cpu.defaultFlags(cpu).contains(CompilationFlag.EmitCmosOpcodes)),
-      "CPUFEATURE_65CE02" -> toLong(Cpu.defaultFlags(cpu).contains(CompilationFlag.Emit65CE02Opcodes)),
+      "CPU_6502" -> toLong(Set(Cpu.Mos, Cpu.StrictMos, Cpu.Ricoh, Cpu.StrictRicoh)(cpu)),
+      "CPU_65C02" -> toLong(cpu == Cpu.Cmos),
+      "CPU_65CE02" -> toLong(cpu == Cpu.CE02),
+      "CPU_65816" -> toLong(cpu == Cpu.Sixteen),
+      "CPU_HUC6280" -> toLong(cpu == Cpu.HuC6280),
       "ARCH_I80" -> toLong(CpuFamily.forType(cpu) == CpuFamily.I80),
-      "CPUFEATURE_Z80" -> toLong(Cpu.defaultFlags(cpu).contains(CompilationFlag.EmitZ80Opcodes)),
-      "CPUFEATURE_8080" -> toLong(Cpu.defaultFlags(cpu).contains(CompilationFlag.EmitIntel8080Opcodes)),
-      "CPUFEATURE_GAMEBOY" -> toLong(Cpu.defaultFlags(cpu).contains(CompilationFlag.EmitSharpOpcodes)),
+      "CPU_Z80" -> toLong(cpu == Cpu.Z80),
+      "CPU_EZ80" -> toLong(cpu == Cpu.EZ80),
+      "CPU_8080" -> toLong(cpu == Cpu.Intel8080),
+      "CPU_GAMEBOY" -> toLong(cpu == Cpu.Sharp),
       "ARCH_X86" -> toLong(CpuFamily.forType(cpu) == CpuFamily.I86),
       "ARCH_6800" -> toLong(CpuFamily.forType(cpu) == CpuFamily.M6800),
       "ARCH_ARM" -> toLong(CpuFamily.forType(cpu) == CpuFamily.ARM),
-      "ARCH_68K" -> toLong(CpuFamily.forType(cpu) == CpuFamily.M68K),
-      "HAS_HARDWARE_MULTIPLY" -> (cpu match {
-        case Cpu.EZ80 => 1L
-        case _ => CpuFamily.forType(cpu) match {
-          case CpuFamily.M6502 | CpuFamily.I80 | CpuFamily.M6800 => 0L
-          case CpuFamily.I86 | CpuFamily.ARM | CpuFamily.M68K => 1L
-        }
-      })
+      "ARCH_68K" -> toLong(CpuFamily.forType(cpu) == CpuFamily.M68K)
       // TODO
     )
   }
diff --git a/src/test/scala/millfork/test/emu/EmuRun.scala b/src/test/scala/millfork/test/emu/EmuRun.scala
index 9deec760..98fb05f4 100644
--- a/src/test/scala/millfork/test/emu/EmuRun.scala
+++ b/src/test/scala/millfork/test/emu/EmuRun.scala
@@ -34,7 +34,7 @@ object EmuRun {
     val source = Files.readAllLines(Paths.get(filename), StandardCharsets.US_ASCII).asScala.mkString("\n")
     val options = CompilationOptions(EmuPlatform.get(millfork.Cpu.Mos), Map(
           CompilationFlag.LenientTextEncoding -> true
-        ), None, 4, JobContext(TestErrorReporting.log, new LabelGenerator))
+        ), None, 4, Map(), JobContext(TestErrorReporting.log, new LabelGenerator))
     val PreprocessingResult(preprocessedSource, features, _) = Preprocessor.preprocessForTest(options, source)
     TestErrorReporting.log.info(s"Parsing $filename")
     MosParser("", preprocessedSource, "", options, features).toAst match {
@@ -139,7 +139,7 @@ class EmuRun(cpu: millfork.Cpu.Value, nodeOptimizations: List[NodeOptimization],
       CompilationFlag.OptimizeForSpeed -> blastProcessing,
       CompilationFlag.OptimizeForSonicSpeed -> blastProcessing
       //      CompilationFlag.CheckIndexOutOfBounds -> true,
-    ), None, 4, JobContext(log, new LabelGenerator))
+    ), None, 4, Map(), JobContext(log, new LabelGenerator))
     log.hasErrors = false
     log.verbosity = 999
     var effectiveSource = source
diff --git a/src/test/scala/millfork/test/emu/EmuZ80Run.scala b/src/test/scala/millfork/test/emu/EmuZ80Run.scala
index 1e23cec7..be9648f9 100644
--- a/src/test/scala/millfork/test/emu/EmuZ80Run.scala
+++ b/src/test/scala/millfork/test/emu/EmuZ80Run.scala
@@ -43,7 +43,7 @@ class EmuZ80Run(cpu: millfork.Cpu.Value, nodeOptimizations: List[NodeOptimizatio
       CompilationFlag.OptimizeForSize -> this.optimizeForSize,
       CompilationFlag.EmitIllegals -> (cpu == millfork.Cpu.Z80),
       CompilationFlag.LenientTextEncoding -> true)
-    val options = CompilationOptions(platform, millfork.Cpu.defaultFlags(cpu).map(_ -> true).toMap ++ extraFlags, None, 0, JobContext(log, new LabelGenerator))
+    val options = CompilationOptions(platform, millfork.Cpu.defaultFlags(cpu).map(_ -> true).toMap ++ extraFlags, None, 0, Map(), JobContext(log, new LabelGenerator))
     log.hasErrors = false
     log.verbosity = 999
     var effectiveSource = source
diff --git a/src/test/scala/millfork/test/emu/ShouldNotCompile.scala b/src/test/scala/millfork/test/emu/ShouldNotCompile.scala
index 5abf66c1..b81d9ff0 100644
--- a/src/test/scala/millfork/test/emu/ShouldNotCompile.scala
+++ b/src/test/scala/millfork/test/emu/ShouldNotCompile.scala
@@ -28,7 +28,7 @@ object ShouldNotCompile extends Matchers {
     val log = TestErrorReporting.log
     println(source)
     val platform = EmuPlatform.get(cpu)
-    val options = CompilationOptions(platform, Map(CompilationFlag.LenientTextEncoding -> true), None, platform.zpRegisterSize, JobContext(log, new LabelGenerator))
+    val options = CompilationOptions(platform, Map(CompilationFlag.LenientTextEncoding -> true), None, platform.zpRegisterSize, Map(), JobContext(log, new LabelGenerator))
     log.hasErrors = false
     log.verbosity = 999
     var effectiveSource = source