diff --git a/codeCore/src/prog8/code/target/c64/C64MachineDefinition.kt b/codeCore/src/prog8/code/target/c64/C64MachineDefinition.kt
index ace08c556..4a8e31e35 100644
--- a/codeCore/src/prog8/code/target/c64/C64MachineDefinition.kt
+++ b/codeCore/src/prog8/code/target/c64/C64MachineDefinition.kt
@@ -17,7 +17,7 @@ class C64MachineDefinition: IMachineDefinition {
     override val PROGRAM_LOAD_ADDRESS = 0x0801u
 
     override val BSSHIGHRAM_START = 0xc000u
-    override val BSSHIGHRAM_END = 0xd000u
+    override val BSSHIGHRAM_END = 0xcfffu
 
     override lateinit var zeropage: Zeropage
     override lateinit var golden: GoldenRam
diff --git a/codeCore/src/prog8/code/target/cx16/CX16MachineDefinition.kt b/codeCore/src/prog8/code/target/cx16/CX16MachineDefinition.kt
index 33acf4480..fec9e8498 100644
--- a/codeCore/src/prog8/code/target/cx16/CX16MachineDefinition.kt
+++ b/codeCore/src/prog8/code/target/cx16/CX16MachineDefinition.kt
@@ -16,7 +16,7 @@ class CX16MachineDefinition: IMachineDefinition {
     override val PROGRAM_LOAD_ADDRESS = 0x0801u
 
     override val BSSHIGHRAM_START = 0xa000u     // hiram bank 1, 8Kb, assumed to be active
-    override val BSSHIGHRAM_END = 0xc000u       // rom starts here.
+    override val BSSHIGHRAM_END = 0xbfffu       // Rom starts at $c000
 
     override lateinit var zeropage: Zeropage
     override lateinit var golden: GoldenRam
diff --git a/codeCore/src/prog8/code/target/pet/PETMachineDefinition.kt b/codeCore/src/prog8/code/target/pet/PETMachineDefinition.kt
index 963f10ad6..469613847 100644
--- a/codeCore/src/prog8/code/target/pet/PETMachineDefinition.kt
+++ b/codeCore/src/prog8/code/target/pet/PETMachineDefinition.kt
@@ -15,8 +15,8 @@ class PETMachineDefinition: IMachineDefinition {
     override val FLOAT_MEM_SIZE = Mflpt5.FLOAT_MEM_SIZE
     override val PROGRAM_LOAD_ADDRESS = 0x0401u
 
-    override val BSSHIGHRAM_START = 0xffffu
-    override val BSSHIGHRAM_END = 0xffffu
+    override val BSSHIGHRAM_START = 0u
+    override val BSSHIGHRAM_END = 0u
 
     override lateinit var zeropage: Zeropage
     override lateinit var golden: GoldenRam
diff --git a/codeGenCpu6502/src/prog8/codegen/cpu6502/ProgramAndVarsGen.kt b/codeGenCpu6502/src/prog8/codegen/cpu6502/ProgramAndVarsGen.kt
index 74a151fc7..ae8c50925 100644
--- a/codeGenCpu6502/src/prog8/codegen/cpu6502/ProgramAndVarsGen.kt
+++ b/codeGenCpu6502/src/prog8/codegen/cpu6502/ProgramAndVarsGen.kt
@@ -176,8 +176,10 @@ internal class ProgramAndVarsGen(
         asmgen.out("; bss sections")
         asmgen.out("PROG8_VARSHIGH_RAMBANK = ${options.varsHighBank ?: 1}")
         if(options.varsHighBank!=null) {
-            if(options.compTarget.machine.BSSHIGHRAM_START == 0u || options.compTarget.machine.BSSHIGHRAM_END==0u) {
-                throw AssemblyError("current compilation target hasn't got the high ram area properly defined")
+            if(options.compTarget.machine.BSSHIGHRAM_START == 0u ||
+                options.compTarget.machine.BSSHIGHRAM_END == 0u ||
+                options.compTarget.machine.BSSHIGHRAM_END <= options.compTarget.machine.BSSHIGHRAM_START) {
+                throw AssemblyError("current compilation target hasn't got the high ram area properly defined or it is simply not available")
             }
             // BSS vars in high ram area, memory() slabs just concatenated at the end of the program.
             if(symboltable.allMemorySlabs.isNotEmpty()) {
@@ -187,7 +189,7 @@ internal class ProgramAndVarsGen(
             asmgen.out("  * = ${options.compTarget.machine.BSSHIGHRAM_START.toHex()}")
             asmgen.out("prog8_bss_section_start")
             asmgen.out("  .dsection BSS")
-            asmgen.out("  .cerror * >= ${options.compTarget.machine.BSSHIGHRAM_END.toHex()}, \"too many variables for BSS section\"")
+            asmgen.out("  .cerror * > ${options.compTarget.machine.BSSHIGHRAM_END.toHex()}, \"too many variables for BSS section\"")
             asmgen.out("prog8_bss_section_size = * - prog8_bss_section_start")
         } else {
             // BSS vars followed by memory() slabs, concatenated at the end of the program.
diff --git a/docs/source/todo.rst b/docs/source/todo.rst
index b6ed95eb0..ac15710be 100644
--- a/docs/source/todo.rst
+++ b/docs/source/todo.rst
@@ -2,6 +2,11 @@
 TODO
 ====
 
+- add -varsgold to put BSS vars into golden ram at $0400 (cx16 only) rather than in high memory. Make sure the 64tass .cerror check still works to guard against overflow
+- add -slabshigh and -slabsgold to also put the memory() slabs into these memory areas (they're now still always part of the prg itself)
+- add -nowarnunused, or %option ignore_unused (module scope), to suppress all warnings about unused symbols. Useful in libraries.
+   put this in all library code, like %option no_symbol_prefixing, and get rid of the "trick" it uses currently to suppress unused symbol warnings for library modules.
+
 - [on branch: shortcircuit] investigate McCarthy evaluation again? this may also reduce code size perhaps for things like if a>4 or a<2 ....
 
 ...