From def06dbc0b844792ab0253e9753a71f1a2258df0 Mon Sep 17 00:00:00 2001
From: Irmen de Jong <irmen@razorvine.net>
Date: Fri, 18 Sep 2020 22:10:20 +0200
Subject: [PATCH] allow address-of to be used as a value for a memory pointer
 variable

---
 compiler/src/prog8/ast/processing/AstChecker.kt          | 8 +++++---
 compiler/src/prog8/compiler/target/c64/codegen/AsmGen.kt | 5 ++++-
 2 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/compiler/src/prog8/ast/processing/AstChecker.kt b/compiler/src/prog8/ast/processing/AstChecker.kt
index a4c58bb1f..810e93d78 100644
--- a/compiler/src/prog8/ast/processing/AstChecker.kt
+++ b/compiler/src/prog8/ast/processing/AstChecker.kt
@@ -584,13 +584,15 @@ internal class AstChecker(private val program: Program,
                     }
                 }
 
-                if(decl.value !is NumericLiteralValue) {
-                    err("value of memory var decl is not a numeric literal (it is a ${decl.value!!.javaClass.simpleName}).", decl.value?.position)
-                } else {
+                if(decl.value is NumericLiteralValue) {
                     val value = decl.value as NumericLiteralValue
                     if (value.type !in IntegerDatatypes || value.number.toInt() < 0 || value.number.toInt() > 65535) {
                         err("memory address must be valid integer 0..\$ffff", decl.value?.position)
                     }
+                } else if(decl.value is AddressOf) {
+                    // we allow this too: the address of another variable
+                } else {
+                    err("value of memory var decl is invalid type.", decl.value?.position)
                 }
             }
         }
diff --git a/compiler/src/prog8/compiler/target/c64/codegen/AsmGen.kt b/compiler/src/prog8/compiler/target/c64/codegen/AsmGen.kt
index 2ad774a2d..8bbcfa30e 100644
--- a/compiler/src/prog8/compiler/target/c64/codegen/AsmGen.kt
+++ b/compiler/src/prog8/compiler/target/c64/codegen/AsmGen.kt
@@ -355,7 +355,10 @@ internal class AsmGen(private val program: Program,
         out("\n; memdefs and kernel subroutines")
         val memvars = statements.filterIsInstance<VarDecl>().filter { it.type==VarDeclType.MEMORY || it.type==VarDeclType.CONST }
         for(m in memvars) {
-            out("  ${m.name} = ${(m.value as NumericLiteralValue).number.toHex()}")
+            if(m.value is NumericLiteralValue)
+                out("  ${m.name} = ${(m.value as NumericLiteralValue).number.toHex()}")
+            else
+                out("  ${m.name} = ${asmVariableName((m.value as AddressOf).identifier)}")
         }
         val asmSubs = statements.filterIsInstance<Subroutine>().filter { it.isAsmSubroutine }
         for(sub in asmSubs) {