Consistently do & alignMask, not % alignSize

Also add more unrelated tests for coverage

test/asm/deprecated-functions.asm

@@ -4,12 +4,25 @@ def s equs "Hello world!"
 assert strin(#s, "l") == strfind(#s, "l") + 1
 assert strrin(#s, "l") == strrfind(#s, "l") + 1
 
-assert !strcmp(strsub(#s, 7), strslice(#s, 6))
-assert !strcmp(strsub(#s, 7, 5), strslice(#s, 6, 11))
-assert !strcmp(strsub(#s, strlen(#s), 1), strslice(#s, strlen(#s) - 1, strlen(#s)))
-assert !strcmp(strsub(#s, 7, 999), strslice(#s, 6, 999))
+assert strsub(#s, 7) === strslice(#s, 6)
+assert strsub(#s, 7, 5) === strslice(#s, 6, 11)
+assert strsub(#s, strlen(#s), 1) === strslice(#s, strlen(#s) - 1, strlen(#s))
+assert strsub(#s, 7, 999) === strslice(#s, 6, 999)
 
-assert !strcmp(charsub(#s, 12), strchar(#s, 11))
-assert !strcmp(charsub(#s, -1), strchar(#s, -1))
-assert !strcmp(charsub(#s, -999), strchar(#s, -999))
-assert !strcmp(charsub(#s, 999), strchar(#s, 999))
+assert charsub(#s, 12) === strchar(#s, 11)
+assert charsub(#s, -1) === strchar(#s, -1)
+assert charsub(#s, -999) === strchar(#s, -999)
+assert charsub(#s, 999) === strchar(#s, 999)
+
+; characters:
+; 1: U+0061 a
+; 2: U+00E4 a with diaresis (0xC3 0xA4)
+; 3: U+0062 b
+; 4: invalid byte 0xA3
+; 5: U+0063 c
+; 6: incomplete U+6F22 kanji (0xE6 0xBC without 0xA2)
+def invalid equs "aäb<C3A4>c<EFBFBD><63>"
+
+def copy equs strsub(#invalid, 1)
+def past equs strsub(#invalid, 9, 1)
+def incomplete equs strsub(#invalid, 12, 1)

test/asm/deprecated-functions.err

@@ -30,3 +30,26 @@ warning: CHARSUB: Position 999 is past the end of the string [-Wbuiltin-args]
     at deprecated-functions.asm(15)
 warning: STRCHAR: Index 999 is past the end of the string [-Wbuiltin-args]
     at deprecated-functions.asm(15)
+warning: `STRSUB` is deprecated; use 0-indexed `STRSLICE` instead [-Wobsolete]
+    at deprecated-functions.asm(26)
+error: STRSUB: Invalid UTF-8 byte 0xA3
+    at deprecated-functions.asm(26)
+error: STRSUB: Incomplete UTF-8 character
+    at deprecated-functions.asm(26)
+warning: `STRSUB` is deprecated; use 0-indexed `STRSLICE` instead [-Wobsolete]
+    at deprecated-functions.asm(27)
+error: STRSUB: Invalid UTF-8 byte 0xA3
+    at deprecated-functions.asm(27)
+warning: STRSUB: Position 9 is past the end of the string [-Wbuiltin-args]
+    at deprecated-functions.asm(27)
+error: STRSUB: Incomplete UTF-8 character
+    at deprecated-functions.asm(27)
+warning: `STRSUB` is deprecated; use 0-indexed `STRSLICE` instead [-Wobsolete]
+    at deprecated-functions.asm(28)
+error: STRSUB: Invalid UTF-8 byte 0xA3
+    at deprecated-functions.asm(28)
+warning: STRSUB: Position 12 is past the end of the string [-Wbuiltin-args]
+    at deprecated-functions.asm(28)
+error: STRSUB: Incomplete UTF-8 character
+    at deprecated-functions.asm(28)
+Assembly aborted with 6 errors!

test/asm/incbin-start-bad.asm

@@ -0,0 +1,4 @@
+SECTION "Bad", ROM0
+
+INCBIN "data.bin", 999
+INCBIN "data.bin", 999, 1

test/asm/incbin-start-bad.err

@@ -0,0 +1,5 @@
+error: Specified start position is greater than length of file "data.bin"
+    at incbin-start-bad.asm(3)
+error: Specified start position is greater than length of file "data.bin"
+    at incbin-start-bad.asm(4)
+Assembly aborted with 2 errors!

test/link/section-fragment/align-conflict.asm

@@ -0,0 +1,10 @@
+IF !DEF(SECOND)
+	def ATTRS equs ",ALIGN[2]"
+ELSE
+	def ATTRS equs "[$1337]"
+ENDC
+
+SECTION FRAGMENT "conflicting alignment", ROM0 {ATTRS}
+	db
+
+	PURGE ATTRS

test/link/section-fragment/align-conflict.out

@@ -0,0 +1,10 @@
+FATAL: Section "conflicting alignment" is defined with 4-byte alignment (offset 0), but also with address $1337
+    at section-fragment/align-conflict.asm(7)
+    and also:
+    at section-fragment/align-conflict.asm(7)
+Linking aborted with 1 error
+---
+error: Section already declared as aligned to 4 bytes (offset 0)
+    at <stdin>(18)
+FATAL: Cannot create section "conflicting alignment" (1 error)
+    at <stdin>(18)

test/link/test.sh

@@ -401,7 +401,7 @@ tryDiff "$test"/out.err "$outtemp"
 tryCmpRom "$test"/ref.out.bin
 evaluateTest
 
-for i in section-union/*.asm; do
+for i in section-union/*.asm section-fragment/*.asm; do
 	test=${i%.asm}
 	startTest
 	"$RGBASM" -o "$otemp" "${test}.asm"