diff --git a/src/asm/parser.y b/src/asm/parser.y
index 41549b603c..8fdcae6671 100644
--- a/src/asm/parser.y
+++ b/src/asm/parser.y
@@ -956,29 +956,58 @@ compoundeq	: T_POP_ADDEQ { $$ = RPN_ADD; }
 		| T_POP_SHREQ { $$ = RPN_SHR; }
 ;
 
-equ		: T_LABEL T_POP_EQU const { sym_AddEqu($1, $3); }
+equ		: T_LABEL T_POP_EQU const {
+			warning(WARNING_OBSOLETE, "`%s EQU` is deprecated; use `DEF %s EQU`\n", $1, $1);
+			sym_AddEqu($1, $3);
+		}
 ;
 
-assignment	: T_LABEL T_POP_EQUAL const { sym_AddVar($1, $3); }
-		| T_LABEL compoundeq const { compoundAssignment($1, $2, $3); }
+assignment	: T_LABEL T_POP_EQUAL const {
+			warning(WARNING_OBSOLETE, "`%s =` is deprecated; use `DEF %s =`\n", $1, $1);
+			sym_AddVar($1, $3);
+		}
+		| T_LABEL compoundeq const {
+			static const char *compoundEqOperators[] = {
+				[RPN_ADD] = "+=",
+				[RPN_SUB] = "-=",
+				[RPN_MUL] = "*=",
+				[RPN_DIV] = "/=",
+				[RPN_MOD] = "%=",
+				[RPN_XOR] = "^=",
+				[RPN_OR] = "|=",
+				[RPN_AND] = "&=",
+				[RPN_SHL] = "<<=",
+				[RPN_SHR] = ">>=",
+			};
+
+			warning(WARNING_OBSOLETE, "`%s %s` is deprecated; use `DEF %s %s`\n",
+				$1, compoundEqOperators[$2], $1, compoundEqOperators[$2]);
+			compoundAssignment($1, $2, $3);
+		}
 ;
 
-equs		: T_LABEL T_POP_EQUS string { sym_AddString($1, $3); }
+equs		: T_LABEL T_POP_EQUS string {
+			warning(WARNING_OBSOLETE, "`%s EQUS` is deprecated; use `DEF %s EQUS`\n", $1, $1);
+			sym_AddString($1, $3);
+		}
 ;
 
 rb		: T_LABEL T_POP_RB rs_uconst {
+			warning(WARNING_OBSOLETE, "`%s RB` is deprecated; use `DEF %s RB`\n", $1, $1);
 			sym_AddEqu($1, sym_GetConstantValue("_RS"));
 			sym_AddVar("_RS", sym_GetConstantValue("_RS") + $3);
 		}
 ;
 
 rw		: T_LABEL T_POP_RW rs_uconst {
+			warning(WARNING_OBSOLETE, "`%s RW` is deprecated; use `DEF %s RW`\n", $1, $1);
 			sym_AddEqu($1, sym_GetConstantValue("_RS"));
 			sym_AddVar("_RS", sym_GetConstantValue("_RS") + 2 * $3);
 		}
 ;
 
 rl		: T_LABEL T_Z80_RL rs_uconst {
+			warning(WARNING_OBSOLETE, "`%s RL` is deprecated; use `DEF %s RL`\n", $1, $1);
 			sym_AddEqu($1, sym_GetConstantValue("_RS"));
 			sym_AddVar("_RS", sym_GetConstantValue("_RS") + 4 * $3);
 		}
diff --git a/test/asm/bracketed-macro-args.asm b/test/asm/bracketed-macro-args.asm
index b0ddce342c..bbbd9d7e43 100644
--- a/test/asm/bracketed-macro-args.asm
+++ b/test/asm/bracketed-macro-args.asm
@@ -10,9 +10,9 @@ ENDM
 
 MACRO mac
 	println \<2__> + \<1_2> + \<\1>
-x = 2
+	def x = 2
 	println \<{d:x}> + \<1_{d:x}> + \<\<\<13>>>
-y equs "NARG"
+	def y equs "NARG"
 	println \<x> + \<1_{d:x}_> + \<\<\<_{y}>>>
 ENDM
 
diff --git a/test/asm/bracketed-symbols.asm b/test/asm/bracketed-symbols.asm
index f6e1dc21a6..b4ccf6fd65 100644
--- a/test/asm/bracketed-symbols.asm
+++ b/test/asm/bracketed-symbols.asm
@@ -1,18 +1,18 @@
-X = 42
+DEF X = 42
 PRINTLN "{X}"
 PRINTLN "{x:X}"
 PRINTLN "{X:X}"
 PRINTLN "{d:X}"
 PRINTLN "{b:X}"
 
-Y equ 1337
+DEF Y EQU 1337
 PRINTLN "{b:Y}"
 
 rsreset
-R rb 0
+DEF R RB 0
 PRINTLN "{d:R}"
 
-S equs "You can't format me!"
+DEF S EQUS "You can't format me!"
 PRINTLN "{X:S}"
 
 SECTION "Test", ROM0
diff --git a/test/asm/builtin-overwrite.asm b/test/asm/builtin-overwrite.asm
index cea61ac8c2..9f09633948 100644
--- a/test/asm/builtin-overwrite.asm
+++ b/test/asm/builtin-overwrite.asm
@@ -2,17 +2,6 @@ macro tickle
 ; There once was a bug where overwriting worked only on the second try, so
 ; try everything twice for good measure
 
-; Skip this syntax for EQUS, as it is invalid
-IF \2
-\1 = 0
-\1 = 0
-PRINTLN \1
-
-\1 EQU 0
-\1 EQU 0
-PRINTLN \1
-ENDC
-
 PURGE \1
 PURGE \1
 PRINTLN \1
diff --git a/test/asm/builtin-overwrite.err b/test/asm/builtin-overwrite.err
index 2b5dc1909f..eb073cdba0 100644
--- a/test/asm/builtin-overwrite.err
+++ b/test/asm/builtin-overwrite.err
@@ -1,57 +1,49 @@
-error: builtin-overwrite.asm(43) -> builtin-overwrite.asm::tickle(7):
-    '__UTC_YEAR__' already defined as constant at <command-line>
-error: builtin-overwrite.asm(43) -> builtin-overwrite.asm::tickle(8):
-    '__UTC_YEAR__' already defined as constant at <command-line>
-error: builtin-overwrite.asm(43) -> builtin-overwrite.asm::tickle(11):
-    '__UTC_YEAR__' already defined at <command-line>
-error: builtin-overwrite.asm(43) -> builtin-overwrite.asm::tickle(12):
-    '__UTC_YEAR__' already defined at <command-line>
-error: builtin-overwrite.asm(43) -> builtin-overwrite.asm::tickle(16):
+error: builtin-overwrite.asm(32) -> builtin-overwrite.asm::tickle(5):
     Built-in symbol '__UTC_YEAR__' cannot be purged
-error: builtin-overwrite.asm(43) -> builtin-overwrite.asm::tickle(17):
+error: builtin-overwrite.asm(32) -> builtin-overwrite.asm::tickle(6):
     Built-in symbol '__UTC_YEAR__' cannot be purged
-error: builtin-overwrite.asm(43) -> builtin-overwrite.asm::tickle(20):
+error: builtin-overwrite.asm(32) -> builtin-overwrite.asm::tickle(9):
     '__UTC_YEAR__' already defined at <command-line>
-error: builtin-overwrite.asm(43) -> builtin-overwrite.asm::tickle(21):
+error: builtin-overwrite.asm(32) -> builtin-overwrite.asm::tickle(10):
     '__UTC_YEAR__' already defined at <command-line>
-error: builtin-overwrite.asm(43) -> builtin-overwrite.asm::tickle(24):
+error: builtin-overwrite.asm(32) -> builtin-overwrite.asm::tickle(13):
     '__UTC_YEAR__' already defined as constant at <command-line>
-error: builtin-overwrite.asm(43) -> builtin-overwrite.asm::tickle(25):
+error: builtin-overwrite.asm(32) -> builtin-overwrite.asm::tickle(14):
     '__UTC_YEAR__' already defined as constant at <command-line>
-error: builtin-overwrite.asm(43) -> builtin-overwrite.asm::tickle(28):
+error: builtin-overwrite.asm(32) -> builtin-overwrite.asm::tickle(17):
     '__UTC_YEAR__' already defined at <command-line>
-error: builtin-overwrite.asm(43) -> builtin-overwrite.asm::tickle(29):
+error: builtin-overwrite.asm(32) -> builtin-overwrite.asm::tickle(18):
     '__UTC_YEAR__' already defined at <command-line>
-error: builtin-overwrite.asm(43) -> builtin-overwrite.asm::tickle(32):
+error: builtin-overwrite.asm(32) -> builtin-overwrite.asm::tickle(21):
     '__UTC_YEAR__' already defined as constant at <command-line>
-error: builtin-overwrite.asm(43) -> builtin-overwrite.asm::tickle(33):
+error: builtin-overwrite.asm(32) -> builtin-overwrite.asm::tickle(22):
     '__UTC_YEAR__' already defined as constant at <command-line>
-error: builtin-overwrite.asm(43) -> builtin-overwrite.asm::tickle(36):
+error: builtin-overwrite.asm(32) -> builtin-overwrite.asm::tickle(25):
     '__UTC_YEAR__' already defined as non-EQUS at <command-line>
-error: builtin-overwrite.asm(43) -> builtin-overwrite.asm::tickle(37):
+error: builtin-overwrite.asm(32) -> builtin-overwrite.asm::tickle(26):
     '__UTC_YEAR__' already defined as non-EQUS at <command-line>
-error: builtin-overwrite.asm(44) -> builtin-overwrite.asm::tickle(16):
+error: builtin-overwrite.asm(33) -> builtin-overwrite.asm::tickle(5):
     Built-in symbol '__ISO_8601_UTC__' cannot be purged
-error: builtin-overwrite.asm(44) -> builtin-overwrite.asm::tickle(17):
+error: builtin-overwrite.asm(33) -> builtin-overwrite.asm::tickle(6):
     Built-in symbol '__ISO_8601_UTC__' cannot be purged
-error: builtin-overwrite.asm(44) -> builtin-overwrite.asm::tickle(20):
+error: builtin-overwrite.asm(33) -> builtin-overwrite.asm::tickle(9):
     '__ISO_8601_UTC__' already defined at <command-line>
-error: builtin-overwrite.asm(44) -> builtin-overwrite.asm::tickle(21):
+error: builtin-overwrite.asm(33) -> builtin-overwrite.asm::tickle(10):
     '__ISO_8601_UTC__' already defined at <command-line>
-error: builtin-overwrite.asm(44) -> builtin-overwrite.asm::tickle(24):
+error: builtin-overwrite.asm(33) -> builtin-overwrite.asm::tickle(13):
     '__ISO_8601_UTC__' already defined as constant at <command-line>
-error: builtin-overwrite.asm(44) -> builtin-overwrite.asm::tickle(25):
+error: builtin-overwrite.asm(33) -> builtin-overwrite.asm::tickle(14):
     '__ISO_8601_UTC__' already defined as constant at <command-line>
-error: builtin-overwrite.asm(44) -> builtin-overwrite.asm::tickle(28):
+error: builtin-overwrite.asm(33) -> builtin-overwrite.asm::tickle(17):
     '__ISO_8601_UTC__' already defined at <command-line>
-error: builtin-overwrite.asm(44) -> builtin-overwrite.asm::tickle(29):
+error: builtin-overwrite.asm(33) -> builtin-overwrite.asm::tickle(18):
     '__ISO_8601_UTC__' already defined at <command-line>
-error: builtin-overwrite.asm(44) -> builtin-overwrite.asm::tickle(32):
+error: builtin-overwrite.asm(33) -> builtin-overwrite.asm::tickle(21):
     '__ISO_8601_UTC__' already defined as constant at <command-line>
-error: builtin-overwrite.asm(44) -> builtin-overwrite.asm::tickle(33):
+error: builtin-overwrite.asm(33) -> builtin-overwrite.asm::tickle(22):
     '__ISO_8601_UTC__' already defined as constant at <command-line>
-error: builtin-overwrite.asm(44) -> builtin-overwrite.asm::tickle(36):
+error: builtin-overwrite.asm(33) -> builtin-overwrite.asm::tickle(25):
     Built-in symbol '__ISO_8601_UTC__' cannot be redefined
-error: builtin-overwrite.asm(44) -> builtin-overwrite.asm::tickle(37):
+error: builtin-overwrite.asm(33) -> builtin-overwrite.asm::tickle(26):
     Built-in symbol '__ISO_8601_UTC__' cannot be redefined
-error: Assembly aborted (28 errors)!
+error: Assembly aborted (24 errors)!
diff --git a/test/asm/builtin-overwrite.out b/test/asm/builtin-overwrite.out
index d7fcfda7bd..f0170b0442 100644
--- a/test/asm/builtin-overwrite.out
+++ b/test/asm/builtin-overwrite.out
@@ -4,8 +4,6 @@ $7C5
 $7C5
 $7C5
 $7C5
-$7C5
-$7C5
 1989-04-21T12:34:56Z
 1989-04-21T12:34:56Z
 1989-04-21T12:34:56Z
diff --git a/test/asm/charlen-charsub.asm b/test/asm/charlen-charsub.asm
index 0fb7f68256..4736d76d06 100644
--- a/test/asm/charlen-charsub.asm
+++ b/test/asm/charlen-charsub.asm
@@ -7,7 +7,7 @@
 
 SECTION "test", ROM0
 
-S EQUS "XBold<NULL>ABC"
+DEF S EQUS "XBold<NULL>ABC"
 
 	assert CHARLEN("{S}") == 6
 	println CHARSUB("{S}", 2)
diff --git a/test/asm/compound-assignment.asm b/test/asm/compound-assignment.asm
index b113795777..279abc17ec 100644
--- a/test/asm/compound-assignment.asm
+++ b/test/asm/compound-assignment.asm
@@ -30,8 +30,8 @@ endm
   try "def ", q
   try "redef ", r
 
-_RS += 100
+def _RS += 100
 println _RS
 
-UnDeFiNeD ^= 300
+def UnDeFiNeD ^= 300
 println UnDeFiNeD
diff --git a/test/asm/compound-assignment.err b/test/asm/compound-assignment.err
index 867deae20a..77b0e3009e 100644
--- a/test/asm/compound-assignment.err
+++ b/test/asm/compound-assignment.err
@@ -1,3 +1,25 @@
+warning: compound-assignment.asm(29) -> compound-assignment.asm::try(4): [-Wobsolete]
+    `p =` is deprecated; use `DEF p =`
+warning: compound-assignment.asm(29) -> compound-assignment.asm::try(6): [-Wobsolete]
+    `p +=` is deprecated; use `DEF p +=`
+warning: compound-assignment.asm(29) -> compound-assignment.asm::try(8): [-Wobsolete]
+    `p -=` is deprecated; use `DEF p -=`
+warning: compound-assignment.asm(29) -> compound-assignment.asm::try(10): [-Wobsolete]
+    `p *=` is deprecated; use `DEF p *=`
+warning: compound-assignment.asm(29) -> compound-assignment.asm::try(12): [-Wobsolete]
+    `p /=` is deprecated; use `DEF p /=`
+warning: compound-assignment.asm(29) -> compound-assignment.asm::try(14): [-Wobsolete]
+    `p %=` is deprecated; use `DEF p %=`
+warning: compound-assignment.asm(29) -> compound-assignment.asm::try(16): [-Wobsolete]
+    `p |=` is deprecated; use `DEF p |=`
+warning: compound-assignment.asm(29) -> compound-assignment.asm::try(18): [-Wobsolete]
+    `p ^=` is deprecated; use `DEF p ^=`
+warning: compound-assignment.asm(29) -> compound-assignment.asm::try(20): [-Wobsolete]
+    `p &=` is deprecated; use `DEF p &=`
+warning: compound-assignment.asm(29) -> compound-assignment.asm::try(22): [-Wobsolete]
+    `p <<=` is deprecated; use `DEF p <<=`
+warning: compound-assignment.asm(29) -> compound-assignment.asm::try(24): [-Wobsolete]
+    `p >>=` is deprecated; use `DEF p >>=`
 error: compound-assignment.asm(36):
     Expected constant expression: 'UnDeFiNeD' is not constant at assembly time
 error: Assembly aborted (1 error)!
diff --git a/test/asm/def.asm b/test/asm/def.asm
index 580fbda8d1..21b8d8c993 100644
--- a/test/asm/def.asm
+++ b/test/asm/def.asm
@@ -28,3 +28,22 @@ redef string equs "there"
 
 redef constant equ 6*9
 	println constant
+
+old_constant EQU 42
+old_string EQUS "hello"
+
+old_variable = 2 + 2
+old_variable += 3
+old_variable *= 4
+old_variable -= 1
+old_variable /= 5
+old_variable %= 7
+old_variable &= $ffff
+old_variable |= %1010
+old_variable ^= &123
+old_variable <<= 2
+old_variable >>= 1
+
+old_byte rb
+old_word rw
+old_long rl
diff --git a/test/asm/def.err b/test/asm/def.err
index e2e1e97894..afdfa613fb 100644
--- a/test/asm/def.err
+++ b/test/asm/def.err
@@ -1,3 +1,35 @@
 error: def.asm(23):
     'constant' already defined at def.asm(10)
+warning: def.asm(32): [-Wobsolete]
+    `old_constant EQU` is deprecated; use `DEF old_constant EQU`
+warning: def.asm(33): [-Wobsolete]
+    `old_string EQUS` is deprecated; use `DEF old_string EQUS`
+warning: def.asm(35): [-Wobsolete]
+    `old_variable =` is deprecated; use `DEF old_variable =`
+warning: def.asm(36): [-Wobsolete]
+    `old_variable +=` is deprecated; use `DEF old_variable +=`
+warning: def.asm(37): [-Wobsolete]
+    `old_variable *=` is deprecated; use `DEF old_variable *=`
+warning: def.asm(38): [-Wobsolete]
+    `old_variable -=` is deprecated; use `DEF old_variable -=`
+warning: def.asm(39): [-Wobsolete]
+    `old_variable /=` is deprecated; use `DEF old_variable /=`
+warning: def.asm(40): [-Wobsolete]
+    `old_variable %=` is deprecated; use `DEF old_variable %=`
+warning: def.asm(41): [-Wobsolete]
+    `old_variable &=` is deprecated; use `DEF old_variable &=`
+warning: def.asm(42): [-Wobsolete]
+    `old_variable |=` is deprecated; use `DEF old_variable |=`
+warning: def.asm(43): [-Wobsolete]
+    `old_variable ^=` is deprecated; use `DEF old_variable ^=`
+warning: def.asm(44): [-Wobsolete]
+    `old_variable <<=` is deprecated; use `DEF old_variable <<=`
+warning: def.asm(45): [-Wobsolete]
+    `old_variable >>=` is deprecated; use `DEF old_variable >>=`
+warning: def.asm(47): [-Wobsolete]
+    `old_byte RB` is deprecated; use `DEF old_byte RB`
+warning: def.asm(48): [-Wobsolete]
+    `old_word RW` is deprecated; use `DEF old_word RW`
+warning: def.asm(49): [-Wobsolete]
+    `old_long RL` is deprecated; use `DEF old_long RL`
 error: Assembly aborted (1 error)!
diff --git a/test/asm/endc-eof-newline.asm b/test/asm/endc-eof-newline.asm
index 588f5c8cc7..b4f7de1476 100644
--- a/test/asm/endc-eof-newline.asm
+++ b/test/asm/endc-eof-newline.asm
@@ -1,8 +1,8 @@
 IF 1
-X = 0
+DEF X = 0
 INCLUDE "endc-eof-newline.inc"
 INCLUDE "endc-eof-newline-else.inc"
-X = 1
+DEF X = 1
 INCLUDE "endc-eof-newline.inc"
 INCLUDE "endc-eof-newline-else.inc"
-ENDC
\ No newline at end of file
+ENDC
diff --git a/test/asm/equ-charmap.asm b/test/asm/equ-charmap.asm
index 917a0573cf..ccb37fd98c 100644
--- a/test/asm/equ-charmap.asm
+++ b/test/asm/equ-charmap.asm
@@ -1,4 +1,4 @@
 	charmap "A", 1
 SECTION "sec", ROM0[0]
-_A_ EQU "A"
+DEF _A_ EQU "A"
 	db _A_
diff --git a/test/asm/equs-macrodef.asm b/test/asm/equs-macrodef.asm
index 449f319a0e..849addc754 100644
--- a/test/asm/equs-macrodef.asm
+++ b/test/asm/equs-macrodef.asm
@@ -1,3 +1,3 @@
-DEFINE equs "MACRO mac\nPRINTLN \"Hello :D\"\nENDM"
+def DEFINE equs "MACRO mac\nPRINTLN \"Hello :D\"\nENDM"
 DEFINE
 	mac
diff --git a/test/asm/equs-nest.asm b/test/asm/equs-nest.asm
index 15f83ab597..8af6da316b 100644
--- a/test/asm/equs-nest.asm
+++ b/test/asm/equs-nest.asm
@@ -1,4 +1,5 @@
-X1 equs "Y1 equs \"\\\"Success!\\\\n\\\"\""
-Y1 equs "Z1"
+; the nested EQUS can't use DEF because Y1 would not be expanded
+def X1 equs "Y1 equs \"\\\"Success!\\\\n\\\"\""
+def Y1 equs "Z1"
 X1
 	PRINT Z1
diff --git a/test/asm/equs-nest.err b/test/asm/equs-nest.err
index e69de29bb2..98200fcd1c 100644
--- a/test/asm/equs-nest.err
+++ b/test/asm/equs-nest.err
@@ -0,0 +1,3 @@
+warning: equs-nest.asm(4): [-Wobsolete]
+    `Z1 EQUS` is deprecated; use `DEF Z1 EQUS`
+while expanding symbol "X1"
diff --git a/test/asm/equs-newline.asm b/test/asm/equs-newline.asm
index 571577ec54..300a770698 100644
--- a/test/asm/equs-newline.asm
+++ b/test/asm/equs-newline.asm
@@ -1,4 +1,4 @@
 
-ACT equs "WARN \"First\"\nWARN \"Second\""
+def ACT equs "WARN \"First\"\nWARN \"Second\""
 	ACT
 	WARN "Third"
diff --git a/test/asm/equs-purge.asm b/test/asm/equs-purge.asm
index 2cd7659c03..83a6b7ed74 100644
--- a/test/asm/equs-purge.asm
+++ b/test/asm/equs-purge.asm
@@ -1,2 +1,2 @@
-BYE equs "PURGE BYE\nWARN \"Crash?\"\n    \n"
+def BYE equs "PURGE BYE\nWARN \"Crash?\"\n    \n"
 BYE
diff --git a/test/asm/equs-recursion.asm b/test/asm/equs-recursion.asm
index 9ca7c997cc..1d3e6ae152 100644
--- a/test/asm/equs-recursion.asm
+++ b/test/asm/equs-recursion.asm
@@ -1,2 +1,2 @@
-recurse EQUS "recurse"
+DEF recurse EQUS "recurse"
 recurse
diff --git a/test/asm/expand-empty-string.asm b/test/asm/expand-empty-string.asm
index f79c01d23c..b1e7e5b50a 100644
--- a/test/asm/expand-empty-string.asm
+++ b/test/asm/expand-empty-string.asm
@@ -1,6 +1,6 @@
 MACRO test
-v equs "X"
-X equs "" ; should not be expanded
+def v equs "X"
+def X equs "" ; should not be expanded
 \1
 ENDM
 	test v 0
diff --git a/test/asm/ff00+c-label.asm b/test/asm/ff00+c-label.asm
index 61370a33aa..0bf48baaf3 100644
--- a/test/asm/ff00+c-label.asm
+++ b/test/asm/ff00+c-label.asm
@@ -1,4 +1,4 @@
-CONSTANT equ 42
+def CONSTANT equ 42
 PRINTLN $ff00 + CONSTANT
 
 SECTION "Overreading much?", ROM0[0]
diff --git a/test/asm/fixed-point-precision.asm b/test/asm/fixed-point-precision.asm
index 757738e915..f7b80923b4 100644
--- a/test/asm/fixed-point-precision.asm
+++ b/test/asm/fixed-point-precision.asm
@@ -1,22 +1,22 @@
-f1 = 3.1
-f2 = 5.2
-pm = MUL(f1, f2)
-pr = 16.12
+def f1 = 3.1
+def f2 = 5.2
+def pm = MUL(f1, f2)
+def pr = 16.12
 	println "`3.1`:   {9.6f:f1} -> ${08x:f1}"
 	println "`5.2`:   {9.6f:f2} -> ${08x:f2}"
 	println "`MUL`:   {9.6f:pm} -> ${08x:pm}"
 	println "`16.12`: {9.6f:pr} -> ${08x:pr}"
 
-fl = 6.283185
+def fl = 6.283185
 	println "`6.283185`: {.6f:fl} -> ${08x:fl}"
 
-fr = MUL(20.0, 0.32)
+def fr = MUL(20.0, 0.32)
 	println "32% of 20 = {f:fr} (~{.2f:fr}) (~~{.0f:fr})"
 
-q8 = 1.25q8
-q16 = 1.25Q16
-q24 = 1.25q.24
+def q8 = 1.25q8
+def q16 = 1.25Q16
+def q24 = 1.25q.24
 	println "Q8 ${x:q8} Q16 ${x:q16} Q24 ${x:q24}"
 
-qerr = 1.25q32
+def qerr = 1.25q32
 	println qerr
diff --git a/test/asm/for.asm b/test/asm/for.asm
index 7d04d01434..72102671b5 100644
--- a/test/asm/for.asm
+++ b/test/asm/for.asm
@@ -26,7 +26,7 @@ endr
 
 for v, 10, -1, -1
 	print "{d:v} "
-v = 42
+	def v = 42
 endr
 	println "-> {d:v}"
 
@@ -36,7 +36,7 @@ purge q
 endr
 	println "-> {d:q}"
 
-s EQUS "x"
+DEF s EQUS "x"
 for {s}, 3, 30, 3
 	print "{d:x} "
 endr
@@ -46,7 +46,7 @@ for v, 10
 	println "{d:v}"
 if v == 3
 purge v
-v equ 42 ; causes a fatal error
+def v equ 42 ; causes a fatal error
 endc
 endr
 	println "-> {d:v}"
diff --git a/test/asm/format-truncation.asm b/test/asm/format-truncation.asm
index e54ddd9e8b..4ab824431e 100644
--- a/test/asm/format-truncation.asm
+++ b/test/asm/format-truncation.asm
@@ -1,6 +1,6 @@
-num equ 42
-fix equ 123.0
-str equs "hello"
+def num equ 42
+def fix equ 123.0
+def str equs "hello"
 
 println "{#0260x:num}"
 println "{#-260x:num}"
diff --git a/test/asm/interpolation-overflow.asm b/test/asm/interpolation-overflow.asm
index aa7813803e..221c1fc53a 100644
--- a/test/asm/interpolation-overflow.asm
+++ b/test/asm/interpolation-overflow.asm
@@ -1,4 +1,4 @@
 ; It seems that \1 was the easiest way to notice the memory corruption that
 ; resulted from this overflow
-x = 0
+def x = 0
 {.99999999f:x}\1
diff --git a/test/asm/interpolation-recursion.asm b/test/asm/interpolation-recursion.asm
index a1e2ba5c46..90c973a1ce 100644
--- a/test/asm/interpolation-recursion.asm
+++ b/test/asm/interpolation-recursion.asm
@@ -1,2 +1,2 @@
-recurse EQUS "\{recurse\}"
+DEF recurse EQUS "\{recurse\}"
 {recurse}
diff --git a/test/asm/interpolation.asm b/test/asm/interpolation.asm
index a5e6b03494..028ee65667 100644
--- a/test/asm/interpolation.asm
+++ b/test/asm/interpolation.asm
@@ -1,13 +1,13 @@
 SECTION "Test", ROM0
 
-NAME equs "ITEM"
-FMT equs "d"
-ZERO_NUM equ 0
-ZERO_STR equs "0"
+def NAME equs "ITEM"
+def FMT equs "d"
+def ZERO_NUM equ 0
+def ZERO_STR equs "0"
 ; Defines INDEX as 100
-INDEX = 1{ZERO_STR}{{FMT}:ZERO_NUM}
+def INDEX = 1{ZERO_STR}{{FMT}:ZERO_NUM}
 ; Defines ITEM_100 as "\"hundredth\""
-{NAME}_{d:INDEX} equs "\"hundredth\""
+def {NAME}_{d:INDEX} equs "\"hundredth\""
 ; Prints "ITEM_100 is hundredth"
 PRINTLN STRCAT("{NAME}_{d:INDEX}", " is ", {NAME}_{d:INDEX})
 ; Purges ITEM_100
diff --git a/test/asm/invalid-utf-8-strings.asm b/test/asm/invalid-utf-8-strings.asm
index 8f6afa525f..b43bda8efd 100644
--- a/test/asm/invalid-utf-8-strings.asm
+++ b/test/asm/invalid-utf-8-strings.asm
@@ -11,13 +11,13 @@
 ; 10: invalid bytes 0xE6 0xF0
 ; 11: invalid byte 0xA2
 ; 12: U+0021 !
-invalid EQUS "aäbæ¼¢,a£¤bæð¢!"
+DEF invalid EQUS "aäbæ¼¢,a£¤bæð¢!"
 
-n = STRLEN("{invalid}")
-copy EQUS STRSUB("{invalid}", 1)
+DEF n = STRLEN("{invalid}")
+DEF copy EQUS STRSUB("{invalid}", 1)
 
 println "\"{invalid}\" == \"{copy}\" ({d:n})"
 
-mid1 EQUS STRSUB("{invalid}", 5, 2)
-mid2 EQUS STRSUB("{invalid}", 9, 1)
+DEF mid1 EQUS STRSUB("{invalid}", 5, 2)
+DEF mid2 EQUS STRSUB("{invalid}", 9, 1)
 println "\"{mid2}{mid1}\""
diff --git a/test/asm/isconst.asm b/test/asm/isconst.asm
index bc8c041c34..4c59c9dac7 100644
--- a/test/asm/isconst.asm
+++ b/test/asm/isconst.asm
@@ -1,10 +1,10 @@
 
-TEST_NUM = 0
+DEF TEST_NUM = 0
 
 MACRO test_expr
-TEST_NUM = TEST_NUM + 1
+	DEF TEST_NUM = TEST_NUM + 1
 
-IS_CONST = ISCONST(\1)
+	DEF IS_CONST = ISCONST(\1)
 	PRINTLN "Test #{d:TEST_NUM}: ISCONST reports {IS_CONST}"
 	IF (\1) || 1 ; Only test if the expression can be evaluated
 		WARN "Test #{d:TEST_NUM}: Compile-time constant"
diff --git a/test/asm/jr-section.asm b/test/asm/jr-section.asm
index 78ce9850e5..bbc9816002 100644
--- a/test/asm/jr-section.asm
+++ b/test/asm/jr-section.asm
@@ -2,5 +2,5 @@ SECTION "Test", ROM0
 
 Label:
 	jr Label
-DIFF equ Label - @
+def DIFF equ Label - @
 	PRINTLN "{DIFF}"
diff --git a/test/asm/label-macro-arg.asm b/test/asm/label-macro-arg.asm
index 7ab45529de..42db8a68d7 100644
--- a/test/asm/label-macro-arg.asm
+++ b/test/asm/label-macro-arg.asm
@@ -1,12 +1,12 @@
 MACRO m1
-x\1
+def x\1
 ENDM
 
-S EQUS "y"
-S2 EQUS "yy"
+DEF S EQUS "y"
+DEF S2 EQUS "yy"
 
 MACRO m2
-S\1
+S\1 ; can't use DEF, so this will EQUS expand
 ENDM
 
 	m1 = 5
@@ -21,12 +21,12 @@ ENDM
 
 
 MACRO test_char
-VAR_DEF equs "sizeof_\1something = 0"
+DEF VAR_DEF equs "DEF sizeof_\1something = 0"
 VAR_DEF
-sizeof_\1something = 1
+DEF sizeof_\1something = 1
 	PURGE VAR_DEF
 
-VAR_PRINT equs "println \"sizeof_\1something equals {sizeof_\1something}\""
+DEF VAR_PRINT equs "println \"sizeof_\1something equals {sizeof_\1something}\""
 	VAR_PRINT
 	PURGE VAR_PRINT
 ENDM
diff --git a/test/asm/label-macro-arg.err b/test/asm/label-macro-arg.err
index 0b3fd3bb52..2ef5822a93 100644
--- a/test/asm/label-macro-arg.err
+++ b/test/asm/label-macro-arg.err
@@ -1,21 +1,21 @@
+warning: label-macro-arg.asm(13) -> label-macro-arg.asm::m2(9): [-Wobsolete]
+    `y =` is deprecated; use `DEF y =`
+warning: label-macro-arg.asm(15) -> label-macro-arg.asm::m2(9): [-Wobsolete]
+    `yy =` is deprecated; use `DEF yy =`
 error: label-macro-arg.asm(38) -> label-macro-arg.asm::test_char(25):
-    syntax error, unexpected =
+    syntax error, unexpected local identifier, expecting identifier
 while expanding symbol "VAR_DEF"
 error: label-macro-arg.asm(38) -> label-macro-arg.asm::test_char(26):
-    syntax error, unexpected =
+    syntax error, unexpected local identifier, expecting identifier
 error: label-macro-arg.asm(38) -> label-macro-arg.asm::test_char(29):
     Interpolated symbol "sizeof_.something" does not exist
 error: label-macro-arg.asm(39) -> label-macro-arg.asm::test_char(25):
-    Label "sizeof_" created outside of a SECTION
+    syntax error, unexpected label, expecting identifier
 while expanding symbol "VAR_DEF"
-error: label-macro-arg.asm(39) -> label-macro-arg.asm::test_char(25):
-    Macro "something" not defined
-error: label-macro-arg.asm(39) -> label-macro-arg.asm::test_char(26):
-    'sizeof_' already defined at label-macro-arg.asm(39) -> label-macro-arg.asm::test_char(25)
 error: label-macro-arg.asm(39) -> label-macro-arg.asm::test_char(26):
-    Macro "something" not defined
+    syntax error, unexpected label, expecting identifier
 error: label-macro-arg.asm(39) -> label-macro-arg.asm::test_char(29):
     Invalid format spec 'sizeof_'
 error: label-macro-arg.asm(39) -> label-macro-arg.asm::test_char(29):
     Interpolated symbol "something" does not exist
-error: Assembly aborted (9 errors)!
+error: Assembly aborted (7 errors)!
diff --git a/test/asm/label-macro-arg.simple.err b/test/asm/label-macro-arg.simple.err
index 7c35be8e18..cd9ef65e49 100644
--- a/test/asm/label-macro-arg.simple.err
+++ b/test/asm/label-macro-arg.simple.err
@@ -1,3 +1,7 @@
+warning: label-macro-arg.asm(13) -> label-macro-arg.asm::m2(9): [-Wobsolete]
+    `y =` is deprecated; use `DEF y =`
+warning: label-macro-arg.asm(15) -> label-macro-arg.asm::m2(9): [-Wobsolete]
+    `yy =` is deprecated; use `DEF yy =`
 error: label-macro-arg.asm(38) -> label-macro-arg.asm::test_char(25):
     Local label 'sizeof_.something' in main scope
 while expanding symbol "VAR_DEF"
diff --git a/test/asm/long-rpn-expression.asm b/test/asm/long-rpn-expression.asm
index f6d5ab77ef..a3a6a62093 100644
--- a/test/asm/long-rpn-expression.asm
+++ b/test/asm/long-rpn-expression.asm
@@ -1,18 +1,18 @@
 SECTION "sec", ROM0
 
-X0 EQUS "0"
+DEF X0 EQUS "0"
 
 MACRO m
-\1 EQUS STRCAT("{X\2}", "+1")
+DEF \1 EQUS STRCAT("{X\2}", "+1")
 ENDM
 
 FOR n, $7E
-n1 = n + 1
+DEF n1 = n + 1
     m X{X:n1}, {X:n}
 ENDR
 
 ; string of 127 zeros separated by plus signs
-X EQUS "{X7E}"
+DEF X EQUS "{X7E}"
 
     db x+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+\
        X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+X+\
diff --git a/test/asm/macro-#.asm b/test/asm/macro-#.asm
index 9d4c6277ef..69b5f1964d 100644
--- a/test/asm/macro-#.asm
+++ b/test/asm/macro-#.asm
@@ -17,8 +17,8 @@ MACRO person
 ENDM
 
 MACRO object
-x = \1
-y = \2
+	DEF x = \1
+	DEF y = \2
 	shift 2
 	person y, x, \#
 ENDM
@@ -30,7 +30,7 @@ MACRO echo
 	println "\#"
 ENDM
 
-R EQUS "S"
+DEF R EQUS "S"
 
 	echo P
 	echo Q,R, {R},  T
diff --git a/test/asm/macro-arg-in-string.asm b/test/asm/macro-arg-in-string.asm
index 552be93ce8..e970c35a75 100644
--- a/test/asm/macro-arg-in-string.asm
+++ b/test/asm/macro-arg-in-string.asm
@@ -16,12 +16,12 @@ MACRO iprint
 	PRINTLN "{\1}"
 ENDM
 
-s EQUS "hello"
+DEF s EQUS "hello"
 	iprint s
 
 MACRO symprint
 	PRINTLN {\1}
 ENDM
 
-hello EQUS "\"goodbye\""
+DEF hello EQUS "\"goodbye\""
 	symprint s
diff --git a/test/asm/macro-argument-limit.asm b/test/asm/macro-argument-limit.asm
index 498d4ebd9d..48cd471fe0 100644
--- a/test/asm/macro-argument-limit.asm
+++ b/test/asm/macro-argument-limit.asm
@@ -1,8 +1,8 @@
 MACRO addargs
-sum = 0
+	def sum = 0
 	rept _NARG
-sum = sum + \1
-	shift
+		def sum = sum + \1
+		shift
 	endr
         dw sum & $FFFF
 	dw (sum >> 16) & $FFFF
diff --git a/test/asm/math.asm b/test/asm/math.asm
index 8bb1cde59f..d56a2f4638 100644
--- a/test/asm/math.asm
+++ b/test/asm/math.asm
@@ -1,12 +1,12 @@
-X equ 0
+def X equ 0
 
 MACRO test
 ; Test RGBASM
-v equs "X +"
+	def v equs "X +"
 	static_assert \#
 	purge v
 ; Test RGBLINK
-v equs "Y +"
+	def v equs "Y +"
 	assert \#
 	purge v
 ENDM
diff --git a/test/asm/minimum-int.asm b/test/asm/minimum-int.asm
index 5c3cfc66fd..e85750c102 100644
--- a/test/asm/minimum-int.asm
+++ b/test/asm/minimum-int.asm
@@ -1,4 +1,4 @@
-m = $8000_0000
+def m = $8000_0000
 assert m == 1 << 31
 assert m == -(1 << 31)
 assert m == (-2)**31
diff --git a/test/asm/multi-line-strings.asm b/test/asm/multi-line-strings.asm
index 02ce0f6741..b3ef78a7f0 100644
--- a/test/asm/multi-line-strings.asm
+++ b/test/asm/multi-line-strings.asm
@@ -1,4 +1,4 @@
-S EQUS "Hello"
+DEF S EQUS "Hello"
 
 PRINT "\"\"\"\n"
 
@@ -24,11 +24,11 @@ ENDM
 	printarg """multi-line
 string argument"""
 
-EMPTY1 EQUS ""
-EMPTY2 EQUS "\ ; comment
+DEF EMPTY1 EQUS ""
+DEF EMPTY2 EQUS "\ ; comment
 "
-EMPTY3 EQUS """"""
-EMPTY4 EQUS """\ ; comment
+DEF EMPTY3 EQUS """"""
+DEF EMPTY4 EQUS """\ ; comment
 """
 	PRINTLN STRCAT("(", "{EMPTY1}", "{EMPTY2}", "{EMPTY3}", "{EMPTY4}", ")")
 
diff --git a/test/asm/multiple-charmaps.asm b/test/asm/multiple-charmaps.asm
index f9e86ebaed..c6ff4edfa5 100644
--- a/test/asm/multiple-charmaps.asm
+++ b/test/asm/multiple-charmaps.asm
@@ -26,8 +26,8 @@ MACRO pop_
 ENDM
 
 MACRO print_mapped
-x = \1
-println "{x}"
+	def x = \1
+	println "{x}"
 ENDM
 
 println "main charmap"
diff --git a/test/asm/nested-brackets.asm b/test/asm/nested-brackets.asm
index 057a9f09cf..0d3b9e39f5 100644
--- a/test/asm/nested-brackets.asm
+++ b/test/asm/nested-brackets.asm
@@ -1,5 +1,5 @@
-STRING equs "OK"
-WRAPPER equs "TRIN"
+def STRING equs "OK"
+def WRAPPER equs "TRIN"
 	PRINTLN "{S{WRAPPER}G}"
 
 	PRINTLN "{S{WRAPPER}G"
diff --git a/test/asm/nested-break.asm b/test/asm/nested-break.asm
index fbf3ab3271..e685005cb8 100644
--- a/test/asm/nested-break.asm
+++ b/test/asm/nested-break.asm
@@ -1,4 +1,4 @@
-n=1
+def n=1
 rept 10
   print "A"
   for x, 10
@@ -12,6 +12,6 @@ rept 10
     break
   endc
   println "Z"
-n=n+1
+def n=n+1
 endr
 println "\nn={d:n} x={d:x}"
diff --git a/test/asm/nested-macrodef.asm b/test/asm/nested-macrodef.asm
index b2f7eb86fe..eaf1d16ac7 100644
--- a/test/asm/nested-macrodef.asm
+++ b/test/asm/nested-macrodef.asm
@@ -1,5 +1,5 @@
 MACRO outer_ok
-definition equs "MACRO inner_ok\nPRINTLN \"Hello!\"\nENDM"
+def definition equs "MACRO inner_ok\nPRINTLN \"Hello!\"\nENDM"
 definition
 	PURGE definition
 ENDM
@@ -9,7 +9,7 @@ ENDM
 
 
 MACRO outer_arg
-definition equs "MACRO inner_arg\nPRINTLN \"outer: \1\\ninner: \\1\"\nENDM"
+def definition equs "MACRO inner_arg\nPRINTLN \"outer: \1\\ninner: \\1\"\nENDM"
 definition
 	PURGE definition
 ENDM
diff --git a/test/asm/overflow.asm b/test/asm/overflow.asm
index be49062f09..209671b52c 100644
--- a/test/asm/overflow.asm
+++ b/test/asm/overflow.asm
@@ -4,38 +4,38 @@ MACRO print_x
 	println x
 ENDM
 
-x = 2147483647
-x = x + 1
+def x = 2147483647
+def x = x + 1
 	dl 2147483647+1
 	print_x
 
-x = -2147483648
-x = x - 1
+def x = -2147483648
+def x = x - 1
 	dl -2147483648-1
 	print_x
 
-x = -2147483648
-x = x * -1
+def x = -2147483648
+def x = x * -1
 	dl -2147483648 * -1
 	print_x
 
-x = -2147483648
-x = x / -1
+def x = -2147483648
+def x = x / -1
 	dl -2147483648 / -1
 	print_x
 
-x = -2147483648
-x = x % -1
+def x = -2147483648
+def x = x % -1
 	dl -2147483648 % -1
 	print_x
 
-x = -1
-x = x << 1
+def x = -1
+def x = x << 1
 	dl -1 << 1
 	print_x
 
-x = 4294967295
-x = 4294967296
+def x = 4294967295
+def x = 4294967296
 
-x = `33333333
-x = `333333333
+def x = `33333333
+def x = `333333333
diff --git a/test/asm/pc-bank.asm b/test/asm/pc-bank.asm
index 4f0c78eb00..4ddd977b7c 100644
--- a/test/asm/pc-bank.asm
+++ b/test/asm/pc-bank.asm
@@ -1,11 +1,11 @@
 SECTION "Fixed bank", ROMX,BANK[42]
 	ldh a, [BANK(@) * 256] ; This should be complained about at assembly time
 
-X = BANK(@)
+	DEF X = BANK(@)
 
 SECTION "Something else", ROMX
-Y = BANK("Fixed bank")
+	DEF Y = BANK("Fixed bank")
 
-    PRINTLN "@: {X}\nStr: {Y}"
+	PRINTLN "@: {X}\nStr: {Y}"
 
-ERR = BANK(@)
+	DEF ERR = BANK(@)
diff --git a/test/asm/raw-macro-args.asm b/test/asm/raw-macro-args.asm
index b633418b01..658ee28a58 100644
--- a/test/asm/raw-macro-args.asm
+++ b/test/asm/raw-macro-args.asm
@@ -12,8 +12,8 @@ MACRO printlit
 	endr
 ENDM
 
-NUM EQU 42
-STR EQUS "str\"ing"
+DEF NUM EQU 42
+DEF STR EQUS "str\"ing"
 
 	printargs NUM
 	printargs "{d:NUM}"
diff --git a/test/asm/redef-equ.asm b/test/asm/redef-equ.asm
index 36abff5ae5..012cdd64e9 100644
--- a/test/asm/redef-equ.asm
+++ b/test/asm/redef-equ.asm
@@ -4,7 +4,7 @@ REDEF n EQU 1
 PRINTLN n
 
 MACRO list
-LIST_NAME EQUS "\1"
+DEF LIST_NAME EQUS "\1"
 DEF LENGTH_{LIST_NAME} EQU 0
 ENDM
 
@@ -19,5 +19,5 @@ ENDM
 	item 9
 	println LENGTH_SQUARES, SQUARES_1, SQUARES_2, SQUARES_3
 
-N EQUS "X"
+DEF N EQUS "X"
 REDEF N EQU 42
diff --git a/test/asm/redef-equs.asm b/test/asm/redef-equs.asm
index 012ec5555c..6b662ef5a0 100644
--- a/test/asm/redef-equs.asm
+++ b/test/asm/redef-equs.asm
@@ -1,10 +1,10 @@
-s EQUS "Hello, "
+DEF s EQUS "Hello, "
 REDEF s EQUS "{s}world!"
 ; prints "Hello, world!"
 PRINTLN "{s}"
 
 MACRO list
-LIST_NAME EQUS "\1"
+DEF LIST_NAME EQUS "\1"
 REDEF {LIST_NAME} EQUS "["
 REPT _NARG - 1
 REDEF {LIST_NAME} EQUS "{{LIST_NAME}}\2;"
@@ -19,5 +19,5 @@ ENDM
 	list FOO, 1, A, 2, B
 	PRINTLN "{FOO}"
 
-N EQU 42
+DEF N EQU 42
 REDEF N EQUS "X"
diff --git a/test/asm/ref-override-bad.asm b/test/asm/ref-override-bad.asm
index ca3277c6d2..6ff87e542e 100644
--- a/test/asm/ref-override-bad.asm
+++ b/test/asm/ref-override-bad.asm
@@ -2,10 +2,10 @@
 SECTION "Bad!", ROM0
 
 	db W
-W equ 0 ; OK
+def W equ 0 ; OK
 
 	db X
-X equs "0" ; Not OK
+def X equs "0" ; Not OK
 
 	db Y
 macro Y ; Not ok
diff --git a/test/asm/ref-override.asm b/test/asm/ref-override.asm
index dfad75bd99..9187b2c906 100644
--- a/test/asm/ref-override.asm
+++ b/test/asm/ref-override.asm
@@ -1,4 +1,4 @@
 SECTION "Test", ROM0[0]
 	db CONSTANT
 
-CONSTANT equ 42
+def CONSTANT equ 42
diff --git a/test/asm/rs.asm b/test/asm/rs.asm
index 694f3f334f..4e747f280d 100644
--- a/test/asm/rs.asm
+++ b/test/asm/rs.asm
@@ -1,7 +1,7 @@
 
-a1 rb 1
-a2 rw 1
-a3 rl 1
+def a1 rb 1
+def a2 rw 1
+def a3 rl 1
 
 PRINTLN "a1 = ", a1
 PRINTLN "a2 = ", a2
@@ -9,9 +9,9 @@ PRINTLN "a3 = ", a3
 PRINTLN "_RS = ", _RS
 
 
-b1 rb 1
-b2 rw 1
-b3 rl 1
+def b1 rb 1
+def b2 rw 1
+def b3 rl 1
 
 PRINTLN "b1 = ", b1
 PRINTLN "b2 = ", b2
@@ -20,9 +20,9 @@ PRINTLN "_RS = ", _RS
 
 
 rsset 42
-c1 rb 1
-c2 rw 1
-c3 rl 1
+def c1 rb 1
+def c2 rw 1
+def c3 rl 1
 
 PRINTLN "c1 = ", c1
 PRINTLN "c2 = ", c2
@@ -31,13 +31,11 @@ PRINTLN "_RS = ", _RS
 
 
 rsreset
-d1 rb 1
-d2 rw 1
-d3 rl 1
+def d1 rb 1
+def d2 rw 1
+def d3 rl 1
 
 PRINTLN "d1 = ", d1
 PRINTLN "d2 = ", d2
 PRINTLN "d3 = ", d3
 PRINTLN "_RS = ", _RS
-
-
diff --git a/test/asm/section-sizeof-startof.asm b/test/asm/section-sizeof-startof.asm
index 371fae01ca..bd09bdc616 100644
--- a/test/asm/section-sizeof-startof.asm
+++ b/test/asm/section-sizeof-startof.asm
@@ -1,33 +1,33 @@
 SECTION "sect", ROMX[$4567], BANK[$23]
 	ds 42
 
-W = BANK("sect")
-X = SIZEOF("sect") ; unknown
-Y = STARTOF("sect")
+DEF W = BANK("sect")
+DEF X = SIZEOF("sect") ; unknown
+DEF Y = STARTOF("sect")
 
 	println "sect1: {W} {X} {Y}"
 
 SECTION "sect2", ROMX
 
-W = BANK("sect")
-X = SIZEOF("sect")
-Y = STARTOF("sect")
+DEF W = BANK("sect")
+DEF X = SIZEOF("sect")
+DEF Y = STARTOF("sect")
 
 	println "sect1: {W} {X} {Y}"
 
 PUSHS
 SECTION FRAGMENT "sect3", ROMX[$4567], BANK[$12]
 
-W = BANK("sect2") ; unknown
-X = SIZEOF("sect2") ; unknown
-Y = STARTOF("sect2") ; unknown
+DEF W = BANK("sect2") ; unknown
+DEF X = SIZEOF("sect2") ; unknown
+DEF Y = STARTOF("sect2") ; unknown
 
 	println "sect2: {W} {X} {Y}"
 
 POPS
 
-W = BANK("sect3")
-X = SIZEOF("sect3") ; unknown
-Y = STARTOF("sect3")
+DEF W = BANK("sect3")
+DEF X = SIZEOF("sect3") ; unknown
+DEF Y = STARTOF("sect3")
 
 	println "sect3: {W} {X} {Y}"
diff --git a/test/asm/section-union.asm b/test/asm/section-union.asm
index a0f74b639f..c4ca29b4cb 100644
--- a/test/asm/section-union.asm
+++ b/test/asm/section-union.asm
@@ -17,11 +17,11 @@ SECTION UNION "test", WRAM0,ALIGN[9]
 
 
 MACRO check_label
-EXPECTED equ \2
+	def EXPECTED equ \2
 	IF \1 == EXPECTED
-RESULT equs "OK!"
+		def RESULT equs "OK!"
 	ELSE
-RESULT equs "expected {EXPECTED}"
+		def RESULT equs "expected {EXPECTED}"
 	ENDC
 	PURGE EXPECTED
 
diff --git a/test/asm/shift-negative.asm b/test/asm/shift-negative.asm
index 41be00bc52..439d19c482 100644
--- a/test/asm/shift-negative.asm
+++ b/test/asm/shift-negative.asm
@@ -1,6 +1,6 @@
 MACRO reverse
 	for i, _NARG
-i = _NARG - i - 1
+		def i = _NARG - i - 1
 		shift i
 		println \1
 		shift -i
diff --git a/test/asm/strfmt.asm b/test/asm/strfmt.asm
index 988835781e..0e7c9a8f1d 100644
--- a/test/asm/strfmt.asm
+++ b/test/asm/strfmt.asm
@@ -1,14 +1,14 @@
-VAL EQUS STRFMT("Hello %s! I am %d years old today!", "world", $f)
+DEF VAL EQUS STRFMT("Hello %s! I am %d years old today!", "world", $f)
 PRINTLN "{VAL}"
 
-N = -42
+DEF N = -42
 PRINTLN STRFMT("signed %010d == unsigned %010u", N, N)
 
-N = 112
-FMT EQUS "X"
+DEF N = 112
+DEF FMT EQUS "X"
 PRINTLN STRFMT("\tdb %#03{s:FMT} %% 26\t; %#03{FMT}", N, N % 26)
 
-TEMPLATE EQUS "\"%s are %s\\n\""
+DEF TEMPLATE EQUS "\"%s are %s\\n\""
 PRINT STRFMT(TEMPLATE, "roses", "red")
 PRINT STRFMT(TEMPLATE, "violets", "blue")
 PRINT STRFMT(TEMPLATE, "void", 0, "extra")
@@ -16,7 +16,7 @@ PRINT STRFMT(TEMPLATE, "void", 0, "extra")
 PRINTLN STRCAT(STRFMT(STRFMT("%%%s.%d%s", "", 9, "f"), 3.14159), \
 	STRFMT(" ~ %s", STRFMT("%s%x", "thr", 238)))
 
-N = 1.23456
+DEF N = 1.23456
 PRINTLN STRFMT("%.f -> %.3f -> %f", N, N, N)
 
 PRINTLN STRFMT("%d eol %", 1)
diff --git a/test/asm/string-formatting.asm b/test/asm/string-formatting.asm
index 4731a5069a..aeed5d1140 100644
--- a/test/asm/string-formatting.asm
+++ b/test/asm/string-formatting.asm
@@ -1,8 +1,8 @@
-n equ 300
-m equ -42
-f equ -123.0456
-pi equ 3.14159
-s equs "hello"
+def n equ 300
+def m equ -42
+def f equ -123.0456
+def pi equ 3.14159
+def s equs "hello"
 
 	println "<{ -6d:n}> <{+06u:n}> <{5x:n}> <{#16b:n}>"
 	println "<{u:m}> <{+3d:m}> <{#016o:m}>"
diff --git a/test/asm/strupr-strlwr.asm b/test/asm/strupr-strlwr.asm
index 6728adeec9..c5fa42258c 100644
--- a/test/asm/strupr-strlwr.asm
+++ b/test/asm/strupr-strlwr.asm
@@ -1,4 +1,4 @@
-foo equs strupr("xii")
-bar equs strlwr("LOL")
+def foo equs strupr("xii")
+def bar equs strlwr("LOL")
 
 	println "foo={foo} bar={bar}"
diff --git a/test/asm/symbol-invalid-macro-arg.asm b/test/asm/symbol-invalid-macro-arg.asm
index 8cad5843f2..80b647028d 100644
--- a/test/asm/symbol-invalid-macro-arg.asm
+++ b/test/asm/symbol-invalid-macro-arg.asm
@@ -1,2 +1,2 @@
-x\0 = 10
+def x\0 = 10
 println x
diff --git a/test/asm/symbol-override.asm b/test/asm/symbol-override.asm
index 969e7d5f91..4b249926fa 100644
--- a/test/asm/symbol-override.asm
+++ b/test/asm/symbol-override.asm
@@ -1,14 +1,14 @@
-V = 0
-V = 1
+def V = 0
+def V = 1
     PRINTLN "V={V}"
 
-W equ 1
-W = 0
+def W equ 1
+def W = 0
 
 rsset 1
-X rb 0
-X = 0
+def X rb 0
+def X = 0
 
 SECTION "Test", ROM0[1]
 Y:
-Y = 0
+def Y = 0
diff --git a/test/asm/syntax-error-lexer-mode.asm b/test/asm/syntax-error-lexer-mode.asm
index 16af9a3c09..f1993eff4f 100644
--- a/test/asm/syntax-error-lexer-mode.asm
+++ b/test/asm/syntax-error-lexer-mode.asm
@@ -1,4 +1,4 @@
-newline equs "\n"
+def newline equs "\n"
 
 def x = 1 newline def y = 2
 println "x={d:x}, y={d:y}"
diff --git a/test/asm/unique-id.asm b/test/asm/unique-id.asm
index c856721415..f5c84419a7 100644
--- a/test/asm/unique-id.asm
+++ b/test/asm/unique-id.asm
@@ -1,4 +1,4 @@
-warn_unique EQUS "WARN \"\\@!\""
+DEF warn_unique EQUS "WARN \"\\@!\""
 
 macro m
     warn_unique
diff --git a/test/asm/utc-time.asm b/test/asm/utc-time.asm
index 30d80fb798..38c56ae6c5 100644
--- a/test/asm/utc-time.asm
+++ b/test/asm/utc-time.asm
@@ -9,6 +9,6 @@ ENDM
 	between 0, __UTC_MINUTE__, 59
 	between 0, __UTC_SECOND__, 60 ; leap seconds!
 
-UTC_TIME EQUS STRCAT("{04d:__UTC_YEAR__}-{02d:__UTC_MONTH__}-{02d:__UTC_DAY__}T", \
+DEF UTC_TIME EQUS STRCAT("{04d:__UTC_YEAR__}-{02d:__UTC_MONTH__}-{02d:__UTC_DAY__}T", \
                      "{02d:__UTC_HOUR__}:{02d:__UTC_MINUTE__}:{02d:__UTC_SECOND__}Z")
 	assert !STRCMP("{UTC_TIME}", __ISO_8601_UTC__)
diff --git a/test/asm/warn-truncation.asm b/test/asm/warn-truncation.asm
index 272dad738c..e394026d9a 100644
--- a/test/asm/warn-truncation.asm
+++ b/test/asm/warn-truncation.asm
@@ -1,5 +1,5 @@
-FOO_F EQU 5
-BAR_F EQU 7
+DEF FOO_F EQU 5
+DEF BAR_F EQU 7
 
 
 SECTION "RAM", WRAMX[$d500]
diff --git a/test/link/all-instructions.asm b/test/link/all-instructions.asm
index bdc744ba9f..0f7eb83052 100644
--- a/test/link/all-instructions.asm
+++ b/test/link/all-instructions.asm
@@ -57,7 +57,7 @@ ENDM
     ; Bit Operations Instructions
 
 MACRO bitop_u3_instruction_list
-NBIT = 0
+    DEF NBIT = 0
     REPT 8
         \1 NBIT,a
         \1 NBIT,b
@@ -67,7 +67,7 @@ NBIT = 0
         \1 NBIT,h
         \1 NBIT,[hl]
         \1 NBIT,l
-NBIT = NBIT + 1
+        DEF NBIT = NBIT + 1
     ENDR
 ENDM
 
diff --git a/test/link/bank-const/a.asm b/test/link/bank-const/a.asm
index 3590ea579b..4656c29c70 100644
--- a/test/link/bank-const/a.asm
+++ b/test/link/bank-const/a.asm
@@ -1,2 +1,2 @@
-CONSTANT equ 0
+def CONSTANT equ 0
 EXPORT CONSTANT
diff --git a/test/link/section-union/align-conflict.asm b/test/link/section-union/align-conflict.asm
index 7a92349be2..c5784e9b53 100644
--- a/test/link/section-union/align-conflict.asm
+++ b/test/link/section-union/align-conflict.asm
@@ -1,7 +1,7 @@
 IF !DEF(SECOND)
-ATTRS equs ",ALIGN[2]"
+	def ATTRS equs ",ALIGN[2]"
 ELSE
-ATTRS equs "[$CAFE]"
+	def ATTRS equs "[$CAFE]"
 ENDC
 
 SECTION UNION "conflicting alignment", WRAM0 ATTRS
diff --git a/test/link/section-union/align-ofs-conflict.asm b/test/link/section-union/align-ofs-conflict.asm
index 144f7e865f..1f32122080 100644
--- a/test/link/section-union/align-ofs-conflict.asm
+++ b/test/link/section-union/align-ofs-conflict.asm
@@ -1,7 +1,7 @@
 IF !DEF(SECOND)
-ATTRS equs ",ALIGN[3,7]"
+	def ATTRS equs ",ALIGN[3,7]"
 ELSE
-ATTRS equs ",ALIGN[4,14]"
+	def ATTRS equs ",ALIGN[4,14]"
 ENDC
 
 SECTION UNION "conflicting alignment", WRAM0 ATTRS
diff --git a/test/link/section-union/assert.asm b/test/link/section-union/assert.asm
index 91b745d7be..969713bd43 100644
--- a/test/link/section-union/assert.asm
+++ b/test/link/section-union/assert.asm
@@ -1,10 +1,10 @@
 IF !DEF(SECOND)
-OFS = 42
+	def OFS = 42
 ELSE
-OFS = 69
+	def OFS = 69
 ENDC
 
-BASE = $C0DE
+def BASE = $C0DE
 
 SECTION UNION "assertions in unions", WRAM0
 IF DEF(SECOND)
diff --git a/test/link/section-union/bad-types.asm b/test/link/section-union/bad-types.asm
index e8c2e5f9b9..efa914d831 100644
--- a/test/link/section-union/bad-types.asm
+++ b/test/link/section-union/bad-types.asm
@@ -1,7 +1,7 @@
 IF !DEF(SECOND)
-TYPE equs "HRAM"
+	def TYPE equs "HRAM"
 ELSE
-TYPE equs "WRAM0"
+	def TYPE equs "WRAM0"
 ENDC
 
 SECTION UNION "conflicting types", TYPE
diff --git a/test/link/section-union/bank-conflict.asm b/test/link/section-union/bank-conflict.asm
index cc5c6aaca9..d14f834a03 100644
--- a/test/link/section-union/bank-conflict.asm
+++ b/test/link/section-union/bank-conflict.asm
@@ -1,5 +1,5 @@
 IF !DEF(SECOND)
-SECOND equs "4"
+	def SECOND equs "4"
 ENDC
 
 SECTION UNION "conflicting banks", WRAMX, BANK[SECOND]
diff --git a/test/link/section-union/data-overlay.asm b/test/link/section-union/data-overlay.asm
index be65b67ec3..049c4f8dbd 100644
--- a/test/link/section-union/data-overlay.asm
+++ b/test/link/section-union/data-overlay.asm
@@ -1,7 +1,7 @@
 IF !DEF(SECOND)
-DATA equs "ds 4"
+	def DATA equs "ds 4"
 ELSE
-DATA equs "db $aa, $bb, $cc, $dd"
+	def DATA equs "db $aa, $bb, $cc, $dd"
 ENDC
 
 SECTION UNION "overlaid data", ROM0
diff --git a/test/link/section-union/different-data.asm b/test/link/section-union/different-data.asm
index ca6b153754..ca5f079872 100644
--- a/test/link/section-union/different-data.asm
+++ b/test/link/section-union/different-data.asm
@@ -1,7 +1,7 @@
 IF !DEF(SECOND)
-DATA = 1
+	def DATA = 1
 ELSE
-DATA = 2
+	def DATA = 2
 ENDC
 
 SECTION UNION "different data", ROM0
diff --git a/test/link/section-union/different-ofs.asm b/test/link/section-union/different-ofs.asm
index a288ba6861..29241e3815 100644
--- a/test/link/section-union/different-ofs.asm
+++ b/test/link/section-union/different-ofs.asm
@@ -1,7 +1,7 @@
 IF !DEF(SECOND)
-ATTRS equs ",ALIGN[3,7]"
+	def ATTRS equs ",ALIGN[3,7]"
 ELSE
-ATTRS equs ",ALIGN[3,6]"
+	def ATTRS equs ",ALIGN[3,6]"
 ENDC
 
 SECTION UNION "conflicting alignment", WRAM0 ATTRS
diff --git a/test/link/section-union/different-size.asm b/test/link/section-union/different-size.asm
index 6514bf9320..f221b08ccb 100644
--- a/test/link/section-union/different-size.asm
+++ b/test/link/section-union/different-size.asm
@@ -1,7 +1,7 @@
 IF !DEF(SECOND)
-SIZE = 69
+	def SIZE = 69
 ELSE
-SIZE = 420
+	def SIZE = 420
 ENDC
 
 SECTION UNION "different section sizes", ROM0
diff --git a/test/link/section-union/different-syntaxes.asm b/test/link/section-union/different-syntaxes.asm
index d261d21f8d..d139952d30 100644
--- a/test/link/section-union/different-syntaxes.asm
+++ b/test/link/section-union/different-syntaxes.asm
@@ -1,7 +1,7 @@
 IF !DEF(SECOND)
-INSTR equs "sbc a"
+	def INSTR equs "sbc a"
 ELSE
-INSTR equs "db $9f"
+	def INSTR equs "db $9f"
 ENDC
 
 SECTION UNION "different syntaxes", ROM0
diff --git a/test/link/section-union/org-conflict.asm b/test/link/section-union/org-conflict.asm
index b51635b38a..151f9e8830 100644
--- a/test/link/section-union/org-conflict.asm
+++ b/test/link/section-union/org-conflict.asm
@@ -1,7 +1,7 @@
 IF !DEF(SECOND)
-ADDR = $BEEF
+	def ADDR = $BEEF
 ELSE
-ADDR = $BABE
+	def ADDR = $BABE
 ENDC
 
 SECTION UNION "conflicting address", SRAM[ADDR]
diff --git a/test/link/section-union/split-data.asm b/test/link/section-union/split-data.asm
index 2ddff42086..fc372fb770 100644
--- a/test/link/section-union/split-data.asm
+++ b/test/link/section-union/split-data.asm
@@ -1,7 +1,7 @@
 IF !DEF(SECOND)
-DATA equs "ds 1\ndb $aa"
+	def DATA equs "ds 1\ndb $aa"
 ELSE
-DATA equs "db $bb\nds 1"
+	def DATA equs "db $bb\nds 1"
 ENDC
 
 SECTION UNION "mutually-overlaid data", ROM0