Make ENDL optional like ENDSECTION (#1538)

Add warning for `LOAD` without `ENDL`

test/asm/endsection-in-load.err

@@ -1,2 +1,5 @@
-FATAL: endsection-in-load.asm(3):
-    Cannot end the section within a `LOAD` block
+warning: endsection-in-load.asm(3): [-Wunterminated-load]
+    `LOAD` block without `ENDL` terminated by `ENDSECTION`
+error: endsection-in-load.asm(4):
+    Found `ENDL` outside of a `LOAD` block
+error: Assembly aborted (1 error)!

test/asm/load-endings.asm

@@ -0,0 +1,51 @@
+MACRO data
+	db SECTION(@), \#
+ENDM
+
+MACRO now_in
+	if strcmp("\1", "nothing")
+		assert !strcmp(SECTION(@), \1)
+	else
+		assert !def(@)
+	endc
+ENDM
+
+now_in nothing
+
+SECTION "A", ROM0
+	now_in "A"
+	data 1
+	LOAD "P", WRAM0
+		now_in "P"
+		data 2
+
+	; LOAD after LOAD
+	LOAD "Q", WRAM0
+		now_in "Q"
+		data 3
+
+; SECTION after LOAD
+SECTION "B", ROM0
+	now_in "B"
+	data 4
+	LOAD "R", WRAM0
+		now_in "R"
+		data 5
+
+		; PUSHS after LOAD
+		PUSHS
+			SECTION "C", ROM0
+				now_in "C"
+				data 6
+				LOAD "S", WRAM0
+					now_in "S"
+					data 7
+
+		; POPS after LOAD
+		POPS
+		now_in "R"
+		data 8
+
+; ENDSECTION after LOAD
+ENDSECTION
+now_in nothing

test/asm/load-endings.err

@@ -0,0 +1,8 @@
+warning: load-endings.asm(23): [-Wunterminated-load]
+    `LOAD` block without `ENDL` terminated by `LOAD`
+warning: load-endings.asm(28): [-Wunterminated-load]
+    `LOAD` block without `ENDL` terminated by `SECTION`
+warning: load-endings.asm(45): [-Wunterminated-load]
+    `LOAD` block without `ENDL` terminated by `POPS`
+warning: load-endings.asm(50): [-Wunterminated-load]
+    `LOAD` block without `ENDL` terminated by `ENDSECTION`

test/asm/load-endings.out.bin

@@ -0,0 +1 @@
+BRRA
PQCS

test/asm/load-in-load.asm

@@ -1,5 +1,5 @@
 SECTION "outer", ROM0
-LOAD "inner", WRAM0
-LOAD "matryoshka", HRAM
-ENDL
-ENDL
+LOAD "inner1", WRAM0 ; starts "inner1"
+LOAD "inner2", HRAM ; ends "inner1", starts "inner2"
+ENDL ; ends "inner2"
+ENDL ; error

test/asm/load-in-load.err

@@ -1,5 +1,5 @@
-error: load-in-load.asm(3):
-    `LOAD` blocks cannot be nested
+warning: load-in-load.asm(3): [-Wunterminated-load]
+    `LOAD` block without `ENDL` terminated by `LOAD`
 error: load-in-load.asm(5):
     Found `ENDL` outside of a `LOAD` block
-error: Assembly aborted (2 errors)!
+error: Assembly aborted (1 error)!

test/asm/nested-bad-interpolation.asm

@@ -1,3 +1,3 @@
 def p = {{a}}
 def q = "{b}"
-def r = "{{c}}"
+def r = "{{c}}"

test/asm/section-in-load.asm

@@ -1,4 +1,4 @@
-SECTION "outer", ROM0
+SECTION "outer1", ROM0
 LOAD "ram", WRAM0
-SECTION "inner", ROM0
+SECTION "outer2", ROM0
 ENDL

test/asm/section-in-load.err

@@ -1,2 +1,5 @@
-FATAL: section-in-load.asm(3):
-    Cannot change the section within a `LOAD` block
+warning: section-in-load.asm(3): [-Wunterminated-load]
+    `LOAD` block without `ENDL` terminated by `SECTION`
+error: section-in-load.asm(4):
+    Found `ENDL` outside of a `LOAD` block
+error: Assembly aborted (1 error)!

test/asm/unterminated-load.asm

@@ -0,0 +1,2 @@
+SECTION "rom", ROM0
+LOAD "ram", WRAM0

test/asm/unterminated-load.err

@@ -0,0 +1,2 @@
+warning: unterminated-load.asm(3): [-Wunterminated-load]
+    `LOAD` block without `ENDL` terminated by EOF