From 626f0fec5498ccb2e20dc7cf2942e85b9523ba2a Mon Sep 17 00:00:00 2001
From: Alex Dowad <alexinbeijing@gmail.com>
Date: Fri, 30 Jul 2021 11:44:18 +0200
Subject: [PATCH] Remove some dead code from mbstring

mbstring has a great deal of dead code. Some common types are:

- Default switch clauses which will never be taken
- If clauses intended to convert codepoints which were not present in
  a conversion table... but the codepoint in question *is* in the table,
  so the if clause is not needed.
- Bounds checks in places where it is not possible for a value to ever
  be out of bounds.
- Checks to see if an unmatched Unicode codepoint is in CP932 extension
  range 3... but every codepoint in range 3 is also in range 2, so no
  codepoint will ever be matched and converted by that code.
---
 ext/mbstring/libmbfl/filters/mbfilter_big5.c  |  4 +-
 .../libmbfl/filters/mbfilter_cp5022x.c        | 48 ++---------
 .../libmbfl/filters/mbfilter_cp51932.c        |  4 +-
 ext/mbstring/libmbfl/filters/mbfilter_cp932.c |  4 +-
 ext/mbstring/libmbfl/filters/mbfilter_cp936.c | 16 +---
 .../libmbfl/filters/mbfilter_euc_cn.c         | 25 +++---
 .../libmbfl/filters/mbfilter_euc_jp.c         |  6 +-
 .../libmbfl/filters/mbfilter_euc_jp_win.c     |  7 +-
 .../libmbfl/filters/mbfilter_euc_kr.c         | 22 ++----
 .../libmbfl/filters/mbfilter_euc_tw.c         |  4 +-
 .../libmbfl/filters/mbfilter_gb18030.c        | 28 ++-----
 ext/mbstring/libmbfl/filters/mbfilter_hz.c    | 27 +++----
 .../libmbfl/filters/mbfilter_iso2022_jp_ms.c  |  4 -
 .../libmbfl/filters/mbfilter_iso2022_kr.c     | 20 ++---
 .../filters/mbfilter_iso2022jp_mobile.c       |  4 -
 ext/mbstring/libmbfl/filters/mbfilter_jis.c   | 15 +---
 ext/mbstring/libmbfl/filters/mbfilter_sjis.c  |  2 -
 .../libmbfl/filters/mbfilter_sjis_2004.c      | 79 ++++++++-----------
 .../libmbfl/filters/mbfilter_sjis_mac.c       | 13 +--
 .../libmbfl/filters/mbfilter_sjis_mobile.c    | 10 ---
 ext/mbstring/libmbfl/filters/mbfilter_uhc.c   |  4 +-
 ext/mbstring/libmbfl/filters/mbfilter_utf7.c  | 26 ++----
 .../libmbfl/filters/mbfilter_utf7imap.c       |  9 +--
 ext/mbstring/libmbfl/filters/mbfilter_utf8.c  |  5 +-
 .../libmbfl/filters/mbfilter_utf8_mobile.c    |  5 +-
 ext/mbstring/libmbfl/mbfl/mbfilter.c          |  2 -
 26 files changed, 108 insertions(+), 285 deletions(-)

diff --git a/ext/mbstring/libmbfl/filters/mbfilter_big5.c b/ext/mbstring/libmbfl/filters/mbfilter_big5.c
index c4f77a26fc4..561ab8c225a 100644
--- a/ext/mbstring/libmbfl/filters/mbfilter_big5.c
+++ b/ext/mbstring/libmbfl/filters/mbfilter_big5.c
@@ -239,9 +239,7 @@ int mbfl_filt_conv_big5_wchar(int c, mbfl_convert_filter *filter)
 		}
 		break;
 
-	default:
-		filter->status = 0;
-		break;
+		EMPTY_SWITCH_DEFAULT_CASE();
 	}
 
 	return 0;
diff --git a/ext/mbstring/libmbfl/filters/mbfilter_cp5022x.c b/ext/mbstring/libmbfl/filters/mbfilter_cp5022x.c
index 7f1994077ab..a69c4c5426a 100644
--- a/ext/mbstring/libmbfl/filters/mbfilter_cp5022x.c
+++ b/ext/mbstring/libmbfl/filters/mbfilter_cp5022x.c
@@ -298,9 +298,7 @@ retry:
 		}
 		break;
 
-	default:
-		filter->status = 0;
-		break;
+		EMPTY_SWITCH_DEFAULT_CASE();
 	}
 
 	return 0;
@@ -322,16 +320,13 @@ static int mbfl_filt_conv_cp5022x_wchar_flush(mbfl_convert_filter *filter)
 
 static int mbfl_filt_conv_wchar_cp50220(int c, mbfl_convert_filter *filter)
 {
-	int mode = MBFL_FILT_TL_HAN2ZEN_KATAKANA | MBFL_FILT_TL_HAN2ZEN_GLUE, second = 0;
+	int mode = MBFL_FILT_TL_HAN2ZEN_KATAKANA | MBFL_FILT_TL_HAN2ZEN_GLUE;
 	bool consumed = false;
 
 	if (filter->cache) {
-		int s = mbfl_convert_kana(filter->cache, c, &consumed, &second, mode);
+		int s = mbfl_convert_kana(filter->cache, c, &consumed, NULL, mode);
 		filter->cache = consumed ? 0 : c;
 		mbfl_filt_conv_wchar_cp50221(s, filter);
-		if (second) {
-			mbfl_filt_conv_wchar_cp50221(second, filter);
-		}
 	} else if (c == 0) {
 		/* This case has to be handled separately, since `filter->cache == 0` means
 		 * no codepoint is cached */
@@ -345,14 +340,11 @@ static int mbfl_filt_conv_wchar_cp50220(int c, mbfl_convert_filter *filter)
 
 static int mbfl_filt_conv_wchar_cp50220_flush(mbfl_convert_filter *filter)
 {
-	int mode = MBFL_FILT_TL_HAN2ZEN_KATAKANA | MBFL_FILT_TL_HAN2ZEN_GLUE, second = 0;
+	int mode = MBFL_FILT_TL_HAN2ZEN_KATAKANA | MBFL_FILT_TL_HAN2ZEN_GLUE;
 
 	if (filter->cache) {
-		int s = mbfl_convert_kana(filter->cache, 0, NULL, &second, mode);
+		int s = mbfl_convert_kana(filter->cache, 0, NULL, NULL, mode);
 		mbfl_filt_conv_wchar_cp50221(s, filter);
-		if (second) {
-			mbfl_filt_conv_wchar_cp50221(s, filter);
-		}
 		filter->cache = 0;
 	}
 
@@ -432,21 +424,6 @@ int mbfl_filt_conv_wchar_cp50221(int c, mbfl_convert_filter *filter)
 			}
 		}
 
-		if (s < 0) {
-			const int cp932ext3_ucs_table_size =
-					cp932ext3_ucs_table_max - cp932ext3_ucs_table_min;
-			const int limit = cp932ext3_ucs_table_size >
-					cp932ext3_eucjp_table_size ?
-						cp932ext3_eucjp_table_size:
-						cp932ext3_ucs_table_size;
-			for (i = 0; i < limit; i++) {
-				if (c == cp932ext3_ucs_table[i]) {
-					s = cp932ext3_eucjp_table[i];
-					break;
-				}
-			}
-		}
-
 		if (c == 0) {
 			s = 0;
 		} else if (s <= 0) {
@@ -564,21 +541,6 @@ int mbfl_filt_conv_wchar_cp50222(int c, mbfl_convert_filter *filter)
 			}
 		}
 
-		if (s <= 0) {
-			const int cp932ext3_ucs_table_size =
-					cp932ext3_ucs_table_max - cp932ext3_ucs_table_min;
-			const int limit = cp932ext3_ucs_table_size >
-					cp932ext3_eucjp_table_size ?
-						cp932ext3_eucjp_table_size:
-						cp932ext3_ucs_table_size;
-			for (i = 0; i < limit; i++) {
-				if (c == cp932ext3_ucs_table[i]) {
-					s = cp932ext3_eucjp_table[i];
-					break;
-				}
-			}
-		}
-
 		if (c == 0) {
 			s = 0;
 		} else if (s <= 0) {
diff --git a/ext/mbstring/libmbfl/filters/mbfilter_cp51932.c b/ext/mbstring/libmbfl/filters/mbfilter_cp51932.c
index 9bfb75fee8c..c0069a93fb9 100644
--- a/ext/mbstring/libmbfl/filters/mbfilter_cp51932.c
+++ b/ext/mbstring/libmbfl/filters/mbfilter_cp51932.c
@@ -163,9 +163,7 @@ mbfl_filt_conv_cp51932_wchar(int c, mbfl_convert_filter *filter)
 		}
 		break;
 
-	default:
-		filter->status = 0;
-		break;
+		EMPTY_SWITCH_DEFAULT_CASE();
 	}
 
 	return 0;
diff --git a/ext/mbstring/libmbfl/filters/mbfilter_cp932.c b/ext/mbstring/libmbfl/filters/mbfilter_cp932.c
index 10559b593be..9c24fa64494 100644
--- a/ext/mbstring/libmbfl/filters/mbfilter_cp932.c
+++ b/ext/mbstring/libmbfl/filters/mbfilter_cp932.c
@@ -203,9 +203,7 @@ mbfl_filt_conv_cp932_wchar(int c, mbfl_convert_filter *filter)
 		}
 		break;
 
-	default:
-		filter->status = 0;
-		break;
+		EMPTY_SWITCH_DEFAULT_CASE();
 	}
 
 	return 0;
diff --git a/ext/mbstring/libmbfl/filters/mbfilter_cp936.c b/ext/mbstring/libmbfl/filters/mbfilter_cp936.c
index c53bfe42a7b..22a759ee79f 100644
--- a/ext/mbstring/libmbfl/filters/mbfilter_cp936.c
+++ b/ext/mbstring/libmbfl/filters/mbfilter_cp936.c
@@ -142,24 +142,16 @@ int mbfl_filt_conv_cp936_wchar(int c, mbfl_convert_filter *filter)
 
 		if (w <= 0) {
 			if (c1 < 0xff && c1 > 0x80 && c >= 0x40 && c < 0xff && c != 0x7f) {
-				w = (c1 - 0x81)*192 + (c - 0x40);
-				if (w >= 0 && w < cp936_ucs_table_size) {
-					w = cp936_ucs_table[w];
-					if (!w)
-						w = MBFL_BAD_INPUT;
-				} else {
-					w = MBFL_BAD_INPUT;
-				}
-				CK((*filter->output_function)(w, filter->data));
+				w = (c1 - 0x81)*192 + c - 0x40;
+				ZEND_ASSERT(w < cp936_ucs_table_size);
+				CK((*filter->output_function)(cp936_ucs_table[w], filter->data));
 			} else {
 				CK((*filter->output_function)(MBFL_BAD_INPUT, filter->data));
 			}
 		}
 		break;
 
-	default:
-		filter->status = 0;
-		break;
+		EMPTY_SWITCH_DEFAULT_CASE();
 	}
 
 	return 0;
diff --git a/ext/mbstring/libmbfl/filters/mbfilter_euc_cn.c b/ext/mbstring/libmbfl/filters/mbfilter_euc_cn.c
index ecde251b119..01c48e433ee 100644
--- a/ext/mbstring/libmbfl/filters/mbfilter_euc_cn.c
+++ b/ext/mbstring/libmbfl/filters/mbfilter_euc_cn.c
@@ -108,19 +108,16 @@ int mbfl_filt_conv_euccn_wchar(int c, mbfl_convert_filter *filter)
 		filter->status = 0;
 		c1 = filter->cache;
 		if (c > 0xA0 && c < 0xFF) {
-			w = (c1 - 0x81)*192 + (c - 0x40);
-			if (w >= 0 && w < cp936_ucs_table_size) {
-				if (w == 0x1864) {
-					w = 0x30FB;
-				} else if (w == 0x186A) {
-					w = 0x2015;
-				} else if ((w >= 0x1921 && w <= 0x192A) || w == 0x1963 || (w >= 0x1C59 && w <= 0x1C7E) || (w >= 0x1DBB && w <= 0x1DC4)) {
-					w = 0;
-				} else {
-					w = cp936_ucs_table[w];
-				}
-			} else {
+			w = (c1 - 0x81)*192 + c - 0x40;
+			ZEND_ASSERT(w < cp936_ucs_table_size);
+			if (w == 0x1864) {
+				w = 0x30FB;
+			} else if (w == 0x186A) {
+				w = 0x2015;
+			} else if ((w >= 0x1921 && w <= 0x192A) || w == 0x1963 || (w >= 0x1C59 && w <= 0x1C7E) || (w >= 0x1DBB && w <= 0x1DC4)) {
 				w = 0;
+			} else {
+				w = cp936_ucs_table[w];
 			}
 
 			if (w <= 0) {
@@ -133,9 +130,7 @@ int mbfl_filt_conv_euccn_wchar(int c, mbfl_convert_filter *filter)
 		}
 		break;
 
-	default:
-		filter->status = 0;
-		break;
+		EMPTY_SWITCH_DEFAULT_CASE();
 	}
 
 	return 0;
diff --git a/ext/mbstring/libmbfl/filters/mbfilter_euc_jp.c b/ext/mbstring/libmbfl/filters/mbfilter_euc_jp.c
index c963716d432..7dd095862ec 100644
--- a/ext/mbstring/libmbfl/filters/mbfilter_euc_jp.c
+++ b/ext/mbstring/libmbfl/filters/mbfilter_euc_jp.c
@@ -166,9 +166,7 @@ mbfl_filt_conv_eucjp_wchar(int c, mbfl_convert_filter *filter)
 		}
 		break;
 
-	default:
-		filter->status = 0;
-		break;
+		EMPTY_SWITCH_DEFAULT_CASE();
 	}
 
 	return 0;
@@ -209,8 +207,6 @@ mbfl_filt_conv_wchar_eucjp(int c, mbfl_convert_filter *filter)
 	if (s <= 0) {
 		if (c == 0xff3c) {	/* FULLWIDTH REVERSE SOLIDUS */
 			s = 0x2140;
-		} else if (c == 0xff5e) {	/* FULLWIDTH TILDE */
-			s = 0x2141;
 		} else if (c == 0x2225) {	/* PARALLEL TO */
 			s = 0x2142;
 		} else if (c == 0xff0d) {	/* FULLWIDTH HYPHEN-MINUS */
diff --git a/ext/mbstring/libmbfl/filters/mbfilter_euc_jp_win.c b/ext/mbstring/libmbfl/filters/mbfilter_euc_jp_win.c
index 02ee1b1c59a..1209e63148f 100644
--- a/ext/mbstring/libmbfl/filters/mbfilter_euc_jp_win.c
+++ b/ext/mbstring/libmbfl/filters/mbfilter_euc_jp_win.c
@@ -167,6 +167,7 @@ int mbfl_filt_conv_eucjpwin_wchar(int c, mbfl_convert_filter *filter)
 		filter->status++;
 		filter->cache = c;
 		break;
+
 	case 4:	/* got 0x8f,  X 0212 second char */
 		filter->status = 0;
 		c1 = filter->cache;
@@ -211,9 +212,7 @@ int mbfl_filt_conv_eucjpwin_wchar(int c, mbfl_convert_filter *filter)
 		}
 		break;
 
-	default:
-		filter->status = 0;
-		break;
+		EMPTY_SWITCH_DEFAULT_CASE();
 	}
 
 	return 0;
@@ -271,8 +270,6 @@ int mbfl_filt_conv_wchar_eucjpwin(int c, mbfl_convert_filter *filter)
 			s1 = 0x213D;
 		} else if (c == 0xff3c) {	/* FULLWIDTH REVERSE SOLIDUS */
 			s1 = 0x2140;
-		} else if (c == 0xff5e) {	/* FULLWIDTH TILDE */
-			s1 = 0x2141;
 		} else if (c == 0x2225) {	/* PARALLEL TO */
 			s1 = 0x2142;
 		} else if (c == 0xff0d) {	/* FULLWIDTH HYPHEN-MINUS */
diff --git a/ext/mbstring/libmbfl/filters/mbfilter_euc_kr.c b/ext/mbstring/libmbfl/filters/mbfilter_euc_kr.c
index a824909f05c..8362138d15a 100644
--- a/ext/mbstring/libmbfl/filters/mbfilter_euc_kr.c
+++ b/ext/mbstring/libmbfl/filters/mbfilter_euc_kr.c
@@ -114,19 +114,13 @@ int mbfl_filt_conv_euckr_wchar(int c, mbfl_convert_filter *filter)
 		}
 		if (flag > 0 && c >= 0xa1 && c <= 0xfe) {
 			if (flag == 1) { /* 1st: 0xa1..0xc6, 2nd: 0x41..0x7a, 0x81..0xfe */
-				w = (c1 - 0xa1)*190 + (c - 0x41);
-				if (w >= 0 && w < uhc2_ucs_table_size) {
-					w = uhc2_ucs_table[w];
-				} else {
-					w = 0;
-				}
+				w = (c1 - 0xa1)*190 + c - 0x41;
+				ZEND_ASSERT(w < uhc2_ucs_table_size);
+				w = uhc2_ucs_table[w];
 			} else { /* 1st: 0xc7..0xc8,0xca..0xfe, 2nd: 0xa1..0xfe */
-				w = (c1 - 0xc7)*94 + (c - 0xa1);
-				if (w >= 0 && w < uhc3_ucs_table_size) {
-					w = uhc3_ucs_table[w];
-				} else {
-					w = 0;
-				}
+				w = (c1 - 0xc7)*94 + c - 0xa1;
+				ZEND_ASSERT(w < uhc3_ucs_table_size);
+				w = uhc3_ucs_table[w];
 			}
 
 			if (w <= 0) {
@@ -138,9 +132,7 @@ int mbfl_filt_conv_euckr_wchar(int c, mbfl_convert_filter *filter)
 		}
 		break;
 
-	default:
-		filter->status = 0;
-		break;
+		EMPTY_SWITCH_DEFAULT_CASE();
 	}
 
 	return 0;
diff --git a/ext/mbstring/libmbfl/filters/mbfilter_euc_tw.c b/ext/mbstring/libmbfl/filters/mbfilter_euc_tw.c
index 187ac8ad9d5..e2c3bceaa50 100644
--- a/ext/mbstring/libmbfl/filters/mbfilter_euc_tw.c
+++ b/ext/mbstring/libmbfl/filters/mbfilter_euc_tw.c
@@ -184,9 +184,7 @@ int mbfl_filt_conv_euctw_wchar(int c, mbfl_convert_filter *filter)
 		}
 		break;
 
-	default:
-		filter->status = 0;
-		break;
+		EMPTY_SWITCH_DEFAULT_CASE();
 	}
 
 	return 0;
diff --git a/ext/mbstring/libmbfl/filters/mbfilter_gb18030.c b/ext/mbstring/libmbfl/filters/mbfilter_gb18030.c
index 5ab2bc15af6..4a8939523a5 100644
--- a/ext/mbstring/libmbfl/filters/mbfilter_gb18030.c
+++ b/ext/mbstring/libmbfl/filters/mbfilter_gb18030.c
@@ -168,15 +168,9 @@ int mbfl_filt_conv_gb18030_wchar(int c, mbfl_convert_filter *filter)
 				(c1 >= 0x81 && c1 <= 0xa0 && c >= 0x40 && c <= 0xfe && c != 0x7f) ||
 				(c1 >= 0xaa && c1 <= 0xfe && c >= 0x40 && c <= 0xa0 && c != 0x7f) ||
 				(c1 >= 0xa8 && c1 <= 0xa9 && c >= 0x40 && c <= 0xa0 && c != 0x7f)) {
-				w = (c1 - 0x81)*192 + (c - 0x40);
-				if (w >= 0 && w < cp936_ucs_table_size) {
-					w = cp936_ucs_table[w];
-					if (!w)
-						w = MBFL_BAD_INPUT;
-				} else {
-					w = MBFL_BAD_INPUT;
-				}
-				CK((*filter->output_function)(w, filter->data));
+				w = (c1 - 0x81)*192 + c - 0x40;
+				ZEND_ASSERT(w < cp936_ucs_table_size);
+				CK((*filter->output_function)(cp936_ucs_table[w], filter->data));
 			} else {
 				CK((*filter->output_function)(MBFL_BAD_INPUT, filter->data));
 			}
@@ -211,10 +205,6 @@ int mbfl_filt_conv_gb18030_wchar(int c, mbfl_convert_filter *filter)
 				w = (((c1 - 0x81)*10 + (c2 - 0x30))*126 + (c3 - 0x81))*10 + (c - 0x30);
 				if (w >= 0 && w <= 39419) {
 					k = mbfl_bisec_srch(w, mbfl_gb2uni_tbl, mbfl_gb_uni_max);
-					if (k < 0) {
-						CK((*filter->output_function)(MBFL_BAD_INPUT, filter->data));
-						return 0;
-					}
 					w += mbfl_gb_uni_ofst[k];
 				} else {
 					CK((*filter->output_function)(MBFL_BAD_INPUT, filter->data));
@@ -227,9 +217,7 @@ int mbfl_filt_conv_gb18030_wchar(int c, mbfl_convert_filter *filter)
 		}
  		break;
 
-	default:
-		filter->status = 0;
-		break;
+		EMPTY_SWITCH_DEFAULT_CASE();
 	}
 
 	return 0;
@@ -370,12 +358,8 @@ int mbfl_filt_conv_wchar_gb18030(int c, mbfl_convert_filter *filter)
 		s1 = c1 + 0x90;
 	}
 
-	if (s <= 0) {
-		if (c == 0) {
-			s = 0;
-		} else {
-			s = -1;
-		}
+	if (c == 0) {
+		s = 0;
 	}
 
 	if (s >= 0) {
diff --git a/ext/mbstring/libmbfl/filters/mbfilter_hz.c b/ext/mbstring/libmbfl/filters/mbfilter_hz.c
index 14edf64a7bb..722d73dd40c 100644
--- a/ext/mbstring/libmbfl/filters/mbfilter_hz.c
+++ b/ext/mbstring/libmbfl/filters/mbfilter_hz.c
@@ -95,20 +95,17 @@ int mbfl_filt_conv_hz_wchar(int c, mbfl_convert_filter *filter)
 		c1 = filter->cache;
 		if (c1 > 0x20 && c1 < 0x7F && c > 0x20 && c < 0x7F) {
 			s = (c1 - 1)*192 + c + 0x40; /* GB2312 */
-			if (s >= 0 && s < cp936_ucs_table_size) {
-				if (s == 0x1864) {
-					w = 0x30FB;
-				} else if (s == 0x186A) {
-					w = 0x2015;
-				} else if (s == 0x186C) {
-					w = 0x2225;
-				} else if ((s >= 0x1920 && s <= 0x192A) || s == 0x1963 || (s >= 0x1C60 && s <= 0x1C7F) || (s >= 0x1DBB && s <= 0x1DC4)) {
-					w = 0;
-				} else {
-					w = cp936_ucs_table[s];
-				}
-			} else {
+			ZEND_ASSERT(s < cp936_ucs_table_size);
+			if (s == 0x1864) {
+				w = 0x30FB;
+			} else if (s == 0x186A) {
+				w = 0x2015;
+			} else if (s == 0x186C) {
+				w = 0x2225;
+			} else if ((s >= 0x1920 && s <= 0x192A) || s == 0x1963 || (s >= 0x1C60 && s <= 0x1C7F) || (s >= 0x1DBB && s <= 0x1DC4)) {
 				w = 0;
+			} else {
+				w = cp936_ucs_table[s];
 			}
 
 			if (w <= 0) {
@@ -139,9 +136,7 @@ int mbfl_filt_conv_hz_wchar(int c, mbfl_convert_filter *filter)
 		}
 		break;
 
-	default:
-		filter->status = 0;
-		break;
+		EMPTY_SWITCH_DEFAULT_CASE();
 	}
 
 	return 0;
diff --git a/ext/mbstring/libmbfl/filters/mbfilter_iso2022_jp_ms.c b/ext/mbstring/libmbfl/filters/mbfilter_iso2022_jp_ms.c
index cc7cd90a1d5..41d4088c475 100644
--- a/ext/mbstring/libmbfl/filters/mbfilter_iso2022_jp_ms.c
+++ b/ext/mbstring/libmbfl/filters/mbfilter_iso2022_jp_ms.c
@@ -258,12 +258,8 @@ int mbfl_filt_conv_wchar_2022jpms(int c, mbfl_convert_filter *filter)
 	if (s1 <= 0) {
 		if (c == 0xA5) { /* YEN SIGN */
 			s1 = 0x216F; /* FULLWIDTH YEN SIGN */
-		} else if (c == 0x203E) { /* OVER LINE */
-			s1 = 0x2131; /* FULLWIDTH MACRON */
 		} else if (c == 0xFF3C) { /* FULLWIDTH REVERSE SOLIDUS */
 			s1 = 0x2140;
-		} else if (c == 0xFF5E) { /* FULLWIDTH TILDE */
-			s1 = 0x2141;
 		} else if (c == 0x2225) { /* PARALLEL TO */
 			s1 = 0x2142;
 		} else if (c == 0xFF0D) { /* FULLWIDTH HYPHEN-MINUS */
diff --git a/ext/mbstring/libmbfl/filters/mbfilter_iso2022_kr.c b/ext/mbstring/libmbfl/filters/mbfilter_iso2022_kr.c
index ba1177a2ea9..f012656b197 100644
--- a/ext/mbstring/libmbfl/filters/mbfilter_iso2022_kr.c
+++ b/ext/mbstring/libmbfl/filters/mbfilter_iso2022_kr.c
@@ -113,19 +113,13 @@ int mbfl_filt_conv_2022kr_wchar(int c, mbfl_convert_filter *filter)
 			if (flag == 1) {
 				if (c1 != 0x22 || c <= 0x65) {
 					w = (c1 - 0x21)*190 + (c - 0x41) + 0x80;
-					if (w >= 0 && w < uhc2_ucs_table_size) {
-						w = uhc2_ucs_table[w];
-					} else {
-						w = 0;
-					}
+					ZEND_ASSERT(w < uhc2_ucs_table_size);
+					w = uhc2_ucs_table[w];
 				}
 			} else {
-				w = (c1 - 0x47)*94 + (c - 0x21);
-				if (w >= 0 && w < uhc3_ucs_table_size) {
-					w = uhc3_ucs_table[w];
-				} else {
-					w = 0;
-				}
+				w = (c1 - 0x47)*94 + c - 0x21;
+				ZEND_ASSERT(w < uhc3_ucs_table_size);
+				w = uhc3_ucs_table[w];
 			}
 
 			if (w <= 0) {
@@ -162,9 +156,7 @@ int mbfl_filt_conv_2022kr_wchar(int c, mbfl_convert_filter *filter)
 		}
 		break;
 
-	default:
-		filter->status = 0;
-		break;
+		EMPTY_SWITCH_DEFAULT_CASE();
 	}
 
 	return 0;
diff --git a/ext/mbstring/libmbfl/filters/mbfilter_iso2022jp_mobile.c b/ext/mbstring/libmbfl/filters/mbfilter_iso2022jp_mobile.c
index febfd84ddc5..3d289f11915 100644
--- a/ext/mbstring/libmbfl/filters/mbfilter_iso2022jp_mobile.c
+++ b/ext/mbstring/libmbfl/filters/mbfilter_iso2022jp_mobile.c
@@ -268,12 +268,8 @@ int mbfl_filt_conv_wchar_2022jp_mobile(int c, mbfl_convert_filter *filter)
 	if (s1 <= 0) {
 		if (c == 0xA5) { /* YEN SIGN */
 			s1 = 0x216F; /* FULLWIDTH YEN SIGN */
-		} else if (c == 0x203E) { /* OVER LINE */
-			s1 = 0x2131; /* FULLWIDTH MACRON */
 		} else if (c == 0xFF3C) { /* FULLWIDTH REVERSE SOLIDUS */
 			s1 = 0x2140;
-		} else if (c == 0xFF5E) { /* FULLWIDTH TILDE */
-			s1 = 0x2141;
 		} else if (c == 0x2225) { /* PARALLEL TO */
 			s1 = 0x2142;
 		} else if (c == 0xFF0D) { /* FULLWIDTH HYPHEN-MINUS */
diff --git a/ext/mbstring/libmbfl/filters/mbfilter_jis.c b/ext/mbstring/libmbfl/filters/mbfilter_jis.c
index 6d876bbdfad..9de18964cce 100644
--- a/ext/mbstring/libmbfl/filters/mbfilter_jis.c
+++ b/ext/mbstring/libmbfl/filters/mbfilter_jis.c
@@ -251,9 +251,7 @@ retry:
 		}
 		break;
 
-	default:
-		filter->status = 0;
-		break;
+		EMPTY_SWITCH_DEFAULT_CASE();
 	}
 
 	return 0;
@@ -318,14 +316,6 @@ mbfl_filt_conv_wchar_jis(int c, mbfl_convert_filter *filter)
 			}
 			filter->status = 0;
 			CK((*filter->output_function)(s, filter->data));
-		} else if (s < 0x100) { /* kana */
-			if ((filter->status & 0xff00) != 0x100) {
-				CK((*filter->output_function)(0x1b, filter->data));		/* ESC */
-				CK((*filter->output_function)(0x28, filter->data));		/* '(' */
-				CK((*filter->output_function)(0x49, filter->data));		/* 'I' */
-			}
-			filter->status = 0x100;
-			CK((*filter->output_function)(s & 0x7f, filter->data));
 		} else if (s < 0x8080) { /* X 0208 */
 			if ((filter->status & 0xff00) != 0x200) {
 				CK((*filter->output_function)(0x1b, filter->data));		/* ESC */
@@ -380,11 +370,10 @@ mbfl_filt_conv_wchar_2022jp(int c, mbfl_convert_filter *filter)
 	} else if (c >= ucs_r_jis_table_min && c < ucs_r_jis_table_max) {
 		s = ucs_r_jis_table[c - ucs_r_jis_table_min];
 	}
+
 	if (s <= 0) {
 		if (c == 0xa5) {			/* YEN SIGN */
 			s = 0x1005c;
-		} else if (c == 0x203e) {	/* OVER LINE */
-			s = 0x1007e;
 		} else if (c == 0xff3c) {	/* FULLWIDTH REVERSE SOLIDUS */
 			s = 0x2140;
 		} else if (c == 0x2225) {	/* PARALLEL TO */
diff --git a/ext/mbstring/libmbfl/filters/mbfilter_sjis.c b/ext/mbstring/libmbfl/filters/mbfilter_sjis.c
index 188f162bf87..ef59026a9ee 100644
--- a/ext/mbstring/libmbfl/filters/mbfilter_sjis.c
+++ b/ext/mbstring/libmbfl/filters/mbfilter_sjis.c
@@ -221,8 +221,6 @@ int mbfl_filt_conv_wchar_sjis(int c, mbfl_convert_filter *filter)
 			s1 = 0x5C;
 		} else if (c == 0xFF3C) { /* FULLWIDTH REVERSE SOLIDUS */
 			s1 = 0x2140;
-		} else if (c == 0xFF5E) { /* FULLWIDTH TILDE */
-			s1 = 0x2141;
 		} else if (c == 0x2225) { /* PARALLEL TO */
 			s1 = 0x2142;
 		} else if (c == 0xFF0D) { /* FULLWIDTH HYPHEN-MINUS */
diff --git a/ext/mbstring/libmbfl/filters/mbfilter_sjis_2004.c b/ext/mbstring/libmbfl/filters/mbfilter_sjis_2004.c
index a1d94693e8f..19602dd9da4 100644
--- a/ext/mbstring/libmbfl/filters/mbfilter_sjis_2004.c
+++ b/ext/mbstring/libmbfl/filters/mbfilter_sjis_2004.c
@@ -209,43 +209,39 @@ int mbfl_filt_conv_jis2004_wchar(int c, mbfl_convert_filter *filter)
 		}
 		w1 = (s1 << 8) | s2;
 
-		if (w1 >= 0x2121) {
-			/* conversion for combining characters */
-			if ((w1 >= 0x2477 && w1 <= 0x2479) || (w1 >= 0x2479 && w1 <= 0x247B) ||
-				(w1 >= 0x2577 && w1 <= 0x257E) || w1 == 0x2678 || w1 == 0x2B44 ||
-				(w1 >= 0x2B48 && w1 <= 0x2B4F) || (w1 >= 0x2B65 && w1 <= 0x2B66)) {
-				k = mbfl_bisec_srch2(w1, jisx0213_u2_key, jisx0213_u2_tbl_len);
-				if (k >= 0) {
-					w = jisx0213_u2_tbl[2*k];
-					CK((*filter->output_function)(w, filter->data));
-					w = jisx0213_u2_tbl[2*k+1];
-				}
+		/* conversion for combining characters */
+		if ((w1 >= 0x2477 && w1 <= 0x2479) || (w1 >= 0x2479 && w1 <= 0x247B) ||
+			(w1 >= 0x2577 && w1 <= 0x257E) || w1 == 0x2678 || w1 == 0x2B44 ||
+			(w1 >= 0x2B48 && w1 <= 0x2B4F) || (w1 >= 0x2B65 && w1 <= 0x2B66)) {
+			k = mbfl_bisec_srch2(w1, jisx0213_u2_key, jisx0213_u2_tbl_len);
+			if (k >= 0) {
+				w = jisx0213_u2_tbl[2*k];
+				CK((*filter->output_function)(w, filter->data));
+				w = jisx0213_u2_tbl[2*k+1];
 			}
-
-			/* conversion for BMP  */
-			if (w <= 0) {
-				w1 = (s1 - 0x21)*94 + s2 - 0x21;
-				if (w1 >= 0 && w1 < jisx0213_ucs_table_size) {
-					w = jisx0213_ucs_table[w1];
-				}
-			}
-
-			/* conversion for CJK Unified Ideographs ext.B (U+2XXXX) */
-			if (w <= 0) {
-				w1 = (s1 << 8) | s2;
-				k = mbfl_bisec_srch2(w1, jisx0213_jis_u5_key, jisx0213_u5_tbl_len);
-				if (k >= 0) {
-					w = jisx0213_jis_u5_tbl[k] + 0x20000;
-				}
-			}
-
-			if (w <= 0) {
-				w = MBFL_BAD_INPUT;
-			}
-			CK((*filter->output_function)(w, filter->data));
-		} else {
-			CK((*filter->output_function)(MBFL_BAD_INPUT, filter->data));
 		}
+
+		/* conversion for BMP  */
+		if (w <= 0) {
+			w1 = (s1 - 0x21)*94 + s2 - 0x21;
+			if (w1 >= 0 && w1 < jisx0213_ucs_table_size) {
+				w = jisx0213_ucs_table[w1];
+			}
+		}
+
+		/* conversion for CJK Unified Ideographs ext.B (U+2XXXX) */
+		if (w <= 0) {
+			w1 = (s1 << 8) | s2;
+			k = mbfl_bisec_srch2(w1, jisx0213_jis_u5_key, jisx0213_u5_tbl_len);
+			if (k >= 0) {
+				w = jisx0213_jis_u5_tbl[k] + 0x20000;
+			}
+		}
+
+		if (w <= 0) {
+			w = MBFL_BAD_INPUT;
+		}
+		CK((*filter->output_function)(w, filter->data));
 		break;
 
 	case 2: /* got 0x8e: EUC-JP-2004 kana */
@@ -297,11 +293,8 @@ int mbfl_filt_conv_jis2004_wchar(int c, mbfl_convert_filter *filter)
 
 			/* check for japanese chars in BMP */
 			s = (s1 + 94 + k)*94 + s2;
-			if (s >= 0 && s < jisx0213_ucs_table_size) {
-				w = jisx0213_ucs_table[s];
-			} else {
-				w = 0;
-			}
+			ZEND_ASSERT(s < jisx0213_ucs_table_size);
+			w = jisx0213_ucs_table[s];
 
 			/* check for japanese chars in CJK Unified Ideographs ext.B (U+2XXXX) */
 			if (w <= 0) {
@@ -408,9 +401,7 @@ int mbfl_filt_conv_jis2004_wchar(int c, mbfl_convert_filter *filter)
 		}
 		break;
 
-	default:
-		filter->status = 0;
-		break;
+		EMPTY_SWITCH_DEFAULT_CASE();
 	}
 
 	return 0;
@@ -543,8 +534,6 @@ retry:
 		} else {
 			s1 = -1;
 		}
-	} else if (s1 >= 0x9980) {
-		s1 = -1;
 	}
 
 	if (s1 >= 0) {
diff --git a/ext/mbstring/libmbfl/filters/mbfilter_sjis_mac.c b/ext/mbstring/libmbfl/filters/mbfilter_sjis_mac.c
index 35d5bee59a8..e8116b6b8bd 100644
--- a/ext/mbstring/libmbfl/filters/mbfilter_sjis_mac.c
+++ b/ext/mbstring/libmbfl/filters/mbfilter_sjis_mac.c
@@ -253,9 +253,7 @@ mbfl_filt_conv_sjis_mac_wchar(int c, mbfl_convert_filter *filter)
 		}
 		break;
 
-	default:
-		filter->status = 0;
-		break;
+		EMPTY_SWITCH_DEFAULT_CASE();
 	}
 
 	return 0;
@@ -287,7 +285,6 @@ mbfl_filt_conv_wchar_sjis_mac(int c, mbfl_convert_filter *filter)
 	//  r: U+FF00 -> U+FFFF
 
 	switch (filter->status) {
-
 	case 1:
 		c1 = filter->cache;
 		filter->cache = 0;
@@ -368,7 +365,6 @@ mbfl_filt_conv_wchar_sjis_mac(int c, mbfl_convert_filter *filter)
 		ZEND_FALLTHROUGH;
 
 	case 0:
-
 		if (c >= ucs_a1_jis_table_min && c < ucs_a1_jis_table_max) {
 			s1 = ucs_a1_jis_table[c - ucs_a1_jis_table_min];
 			if (c == 0x5c) {
@@ -480,7 +476,6 @@ mbfl_filt_conv_wchar_sjis_mac(int c, mbfl_convert_filter *filter)
 		}
 		break;
 
-
 	case 2:
 		c1 = filter->cache;
 		filter->cache = 0;
@@ -516,7 +511,6 @@ mbfl_filt_conv_wchar_sjis_mac(int c, mbfl_convert_filter *filter)
 			CK(mbfl_filt_conv_illegal_output(c1, filter));
 			return mbfl_filt_conv_wchar_sjis_mac(c, filter);
 		}
-
 		break;
 
 	case 3:
@@ -653,10 +647,9 @@ mbfl_filt_conv_wchar_sjis_mac(int c, mbfl_convert_filter *filter)
 		}
 		break;
 
-	default:
-		filter->status = 0;
-		break;
+		EMPTY_SWITCH_DEFAULT_CASE();
 	}
+
 	return 0;
 }
 
diff --git a/ext/mbstring/libmbfl/filters/mbfilter_sjis_mobile.c b/ext/mbstring/libmbfl/filters/mbfilter_sjis_mobile.c
index 41097df304a..4eaa1c25575 100644
--- a/ext/mbstring/libmbfl/filters/mbfilter_sjis_mobile.c
+++ b/ext/mbstring/libmbfl/filters/mbfilter_sjis_mobile.c
@@ -785,16 +785,6 @@ int mbfl_filt_conv_wchar_sjis_mobile(int c, mbfl_convert_filter *filter)
 			}
 		}
 
-		if (s1 <= 0) {
-			/* CP932 vendor ext3 (115ku - 119ku) */
-			for (c1 = 0; c1 < cp932ext3_ucs_table_max - cp932ext3_ucs_table_min; c1++) {
-				if (c == cp932ext3_ucs_table[c1]) {
-					s1 = (((c1 / 94) + 0x93) << 8) + (c1 % 94) + 0x21;
-					break;
-				}
-			}
-		}
-
 		if (c == 0) {
 			s1 = 0;
 		}
diff --git a/ext/mbstring/libmbfl/filters/mbfilter_uhc.c b/ext/mbstring/libmbfl/filters/mbfilter_uhc.c
index 96be552729b..06300404b6e 100644
--- a/ext/mbstring/libmbfl/filters/mbfilter_uhc.c
+++ b/ext/mbstring/libmbfl/filters/mbfilter_uhc.c
@@ -133,9 +133,7 @@ int mbfl_filt_conv_uhc_wchar(int c, mbfl_convert_filter *filter)
 		CK((*filter->output_function)(w, filter->data));
 		break;
 
-	default:
-		filter->status = 0;
-		break;
+		EMPTY_SWITCH_DEFAULT_CASE();
 	}
 
 	return 0;
diff --git a/ext/mbstring/libmbfl/filters/mbfilter_utf7.c b/ext/mbstring/libmbfl/filters/mbfilter_utf7.c
index a5446afd8ae..c3144b47795 100644
--- a/ext/mbstring/libmbfl/filters/mbfilter_utf7.c
+++ b/ext/mbstring/libmbfl/filters/mbfilter_utf7.c
@@ -163,11 +163,7 @@ int mbfl_filt_conv_utf7_wchar(int c, mbfl_convert_filter *filter)
 				s &= 0x3ff;
 				s |= (filter->cache & 0xfff0000) >> 6;
 				filter->cache = n;
-				if (s >= MBFL_WCSPLANE_SUPMIN && s < MBFL_WCSPLANE_SUPMAX) {
-					CK((*filter->output_function)(s, filter->data));
-				} else { /* illegal character */
-					CK((*filter->output_function)(MBFL_BAD_INPUT, filter->data));
-				}
+				CK((*filter->output_function)(s, filter->data));
 			} else {
 				CK((*filter->output_function)(MBFL_BAD_INPUT, filter->data));
 				filter->cache = n;
@@ -207,11 +203,7 @@ int mbfl_filt_conv_utf7_wchar(int c, mbfl_convert_filter *filter)
 				s &= 0x3ff;
 				s |= (filter->cache & 0xfff0000) >> 6;
 				filter->cache = n;
-				if (s >= MBFL_WCSPLANE_SUPMIN && s < MBFL_WCSPLANE_SUPMAX) {
-					CK((*filter->output_function)(s, filter->data));
-				} else { /* illegal character */
-					CK((*filter->output_function)(MBFL_BAD_INPUT, filter->data));
-				}
+				CK((*filter->output_function)(s, filter->data));
 			} else {
 				CK((*filter->output_function)(MBFL_BAD_INPUT, filter->data));
 				filter->cache = n;
@@ -245,11 +237,7 @@ int mbfl_filt_conv_utf7_wchar(int c, mbfl_convert_filter *filter)
 				s &= 0x3ff;
 				s |= (filter->cache & 0xfff0000) >> 6;
 				filter->cache = 0;
-				if (s >= MBFL_WCSPLANE_SUPMIN && s < MBFL_WCSPLANE_SUPMAX) {
-					CK((*filter->output_function)(s, filter->data));
-				} else { /* illegal character */
-					CK((*filter->output_function)(MBFL_BAD_INPUT, filter->data));
-				}
+				CK((*filter->output_function)(s, filter->data));
 			} else {
 				CK((*filter->output_function)(MBFL_BAD_INPUT, filter->data));
 				filter->cache = 0;
@@ -264,9 +252,7 @@ int mbfl_filt_conv_utf7_wchar(int c, mbfl_convert_filter *filter)
 		}
 		break;
 
-	default:
-		filter->status = 0;
-		break;
+		EMPTY_SWITCH_DEFAULT_CASE();
 	}
 
 	return 0;
@@ -373,9 +359,7 @@ int mbfl_filt_conv_wchar_utf7(int c, mbfl_convert_filter *filter)
 		}
 		break;
 
-	default:
-		filter->status = 0;
-		break;
+		EMPTY_SWITCH_DEFAULT_CASE();
 	}
 
 	return 0;
diff --git a/ext/mbstring/libmbfl/filters/mbfilter_utf7imap.c b/ext/mbstring/libmbfl/filters/mbfilter_utf7imap.c
index eb768f9ab2b..473a1f56c13 100644
--- a/ext/mbstring/libmbfl/filters/mbfilter_utf7imap.c
+++ b/ext/mbstring/libmbfl/filters/mbfilter_utf7imap.c
@@ -269,9 +269,7 @@ int mbfl_filt_conv_utf7imap_wchar(int c, mbfl_convert_filter *filter)
 		}
 		break;
 
-	default:
-		filter->status = 0;
-		break;
+		EMPTY_SWITCH_DEFAULT_CASE();
 	}
 
 	return 0;
@@ -397,9 +395,7 @@ int mbfl_filt_conv_wchar_utf7imap(int c, mbfl_convert_filter *filter)
 		}
 		break;
 
-	default:
-		filter->status = 0;
-		break;
+		EMPTY_SWITCH_DEFAULT_CASE();
 	}
 
 	return 0;
@@ -434,5 +430,6 @@ static int mbfl_filt_conv_wchar_utf7imap_flush(mbfl_convert_filter *filter)
 		CK((*filter->output_function)('-', filter->data));
 		break;
 	}
+
 	return 0;
 }
diff --git a/ext/mbstring/libmbfl/filters/mbfilter_utf8.c b/ext/mbstring/libmbfl/filters/mbfilter_utf8.c
index 524c9c079a1..7c371d2e4d1 100644
--- a/ext/mbstring/libmbfl/filters/mbfilter_utf8.c
+++ b/ext/mbstring/libmbfl/filters/mbfilter_utf8.c
@@ -172,9 +172,8 @@ retry:
 			}
 		}
 		break;
-	default:
-		filter->status = 0;
-		break;
+
+		EMPTY_SWITCH_DEFAULT_CASE();
 	}
 
 	return 0;
diff --git a/ext/mbstring/libmbfl/filters/mbfilter_utf8_mobile.c b/ext/mbstring/libmbfl/filters/mbfilter_utf8_mobile.c
index c52459dc3ab..14b00945924 100644
--- a/ext/mbstring/libmbfl/filters/mbfilter_utf8_mobile.c
+++ b/ext/mbstring/libmbfl/filters/mbfilter_utf8_mobile.c
@@ -261,9 +261,8 @@ retry:
 			goto retry;
 		}
 		break;
-	default:
-		filter->status = 0;
-		break;
+
+		EMPTY_SWITCH_DEFAULT_CASE();
 	}
 
 	return 0;
diff --git a/ext/mbstring/libmbfl/mbfl/mbfilter.c b/ext/mbstring/libmbfl/mbfl/mbfilter.c
index 9db80c8895b..a6dfded40a6 100644
--- a/ext/mbstring/libmbfl/mbfl/mbfilter.c
+++ b/ext/mbstring/libmbfl/mbfl/mbfilter.c
@@ -2480,8 +2480,6 @@ int mbfl_filt_decode_htmlnumericentity_flush(mbfl_convert_filter *filter)
 				(*pc->decoder->filter_function)(mbfl_hexchar_table[d], pc->decoder);
 			}
 			break;
-		default:
-			break;
 		}
 	}