diff --git a/src/misc2.c b/src/misc2.c
index acb04b6..fc500e7 100644
--- a/src/misc2.c
+++ b/src/misc2.c
@@ -1885,9 +1885,12 @@
     {
 	while (*p != NUL)
 	{
-	    if (utf_ptr2char(p) == c)
+	    int l = (*mb_ptr2len)(p);
+
+	    /* Avoid matching an illegal byte here. */
+	    if (utf_ptr2char(p) == c && l > 1)
 		return p;
-	    p += (*mb_ptr2len)(p);
+	    p += l;
 	}
 	return NULL;
     }
diff --git a/src/regexp.c b/src/regexp.c
index 961796b..6ae05f8 100644
--- a/src/regexp.c
+++ b/src/regexp.c
@@ -845,13 +845,14 @@
 #else
 	switch (c)
 	{
-	    case 'A': case '\300': case '\301': case '\302':
+	    /* Do not use '\300' style, it results in a negative number. */
+	    case 'A': case 0xc0: case 0xc1: case 0xc2:
+	    case 0xc3: case 0xc4: case 0xc5:
 	    CASEMBC(0x100) CASEMBC(0x102) CASEMBC(0x104) CASEMBC(0x1cd)
 	    CASEMBC(0x1de) CASEMBC(0x1e0) CASEMBC(0x1ea2)
-	    case '\303': case '\304': case '\305':
-		      regmbc('A'); regmbc('\300'); regmbc('\301');
-		      regmbc('\302'); regmbc('\303'); regmbc('\304');
-		      regmbc('\305');
+		      regmbc('A'); regmbc(0xc0); regmbc(0xc1);
+		      regmbc(0xc2); regmbc(0xc3); regmbc(0xc4);
+		      regmbc(0xc5);
 		      REGMBC(0x100) REGMBC(0x102) REGMBC(0x104)
 		      REGMBC(0x1cd) REGMBC(0x1de) REGMBC(0x1e0)
 		      REGMBC(0x1ea2)
@@ -859,9 +860,9 @@
 	    case 'B': CASEMBC(0x1e02) CASEMBC(0x1e06)
 		      regmbc('B'); REGMBC(0x1e02) REGMBC(0x1e06)
 		      return;
-	    case 'C': case '\307':
+	    case 'C': case 0xc7:
 	    CASEMBC(0x106) CASEMBC(0x108) CASEMBC(0x10a) CASEMBC(0x10c)
-		      regmbc('C'); regmbc('\307');
+		      regmbc('C'); regmbc(0xc7);
 		      REGMBC(0x106) REGMBC(0x108) REGMBC(0x10a)
 		      REGMBC(0x10c)
 		      return;
@@ -870,11 +871,11 @@
 		      regmbc('D'); REGMBC(0x10e) REGMBC(0x110)
 		      REGMBC(0x1e0a) REGMBC(0x1e0e) REGMBC(0x1e10)
 		      return;
-	    case 'E': case '\310': case '\311': case '\312': case '\313':
+	    case 'E': case 0xc8: case 0xc9: case 0xca: case 0xcb:
 	    CASEMBC(0x112) CASEMBC(0x114) CASEMBC(0x116) CASEMBC(0x118)
 	    CASEMBC(0x11a) CASEMBC(0x1eba) CASEMBC(0x1ebc)
-		      regmbc('E'); regmbc('\310'); regmbc('\311');
-		      regmbc('\312'); regmbc('\313');
+		      regmbc('E'); regmbc(0xc8); regmbc(0xc9);
+		      regmbc(0xca); regmbc(0xcb);
 		      REGMBC(0x112) REGMBC(0x114) REGMBC(0x116)
 		      REGMBC(0x118) REGMBC(0x11a) REGMBC(0x1eba)
 		      REGMBC(0x1ebc)
@@ -894,11 +895,11 @@
 		      regmbc('H'); REGMBC(0x124) REGMBC(0x126)
 		      REGMBC(0x1e22) REGMBC(0x1e26) REGMBC(0x1e28)
 		      return;
-	    case 'I': case '\314': case '\315': case '\316': case '\317':
+	    case 'I': case 0xcc: case 0xcd: case 0xce: case 0xcf:
 	    CASEMBC(0x128) CASEMBC(0x12a) CASEMBC(0x12c) CASEMBC(0x12e)
 	    CASEMBC(0x130) CASEMBC(0x1cf) CASEMBC(0x1ec8)
-		      regmbc('I'); regmbc('\314'); regmbc('\315');
-		      regmbc('\316'); regmbc('\317');
+		      regmbc('I'); regmbc(0xcc); regmbc(0xcd);
+		      regmbc(0xce); regmbc(0xcf);
 		      REGMBC(0x128) REGMBC(0x12a) REGMBC(0x12c)
 		      REGMBC(0x12e) REGMBC(0x130) REGMBC(0x1cf)
 		      REGMBC(0x1ec8)
@@ -920,20 +921,20 @@
 	    case 'M': CASEMBC(0x1e3e) CASEMBC(0x1e40)
 		      regmbc('M'); REGMBC(0x1e3e) REGMBC(0x1e40)
 		      return;
-	    case 'N': case '\321':
+	    case 'N': case 0xd1:
 	    CASEMBC(0x143) CASEMBC(0x145) CASEMBC(0x147) CASEMBC(0x1e44)
 	    CASEMBC(0x1e48)
-		      regmbc('N'); regmbc('\321');
+		      regmbc('N'); regmbc(0xd1);
 		      REGMBC(0x143) REGMBC(0x145) REGMBC(0x147)
 		      REGMBC(0x1e44) REGMBC(0x1e48)
 		      return;
-	    case 'O': case '\322': case '\323': case '\324': case '\325':
-	    case '\326': case '\330':
+	    case 'O': case 0xd2: case 0xd3: case 0xd4: case 0xd5:
+	    case 0xd6: case 0xd8:
 	    CASEMBC(0x14c) CASEMBC(0x14e) CASEMBC(0x150) CASEMBC(0x1a0)
 	    CASEMBC(0x1d1) CASEMBC(0x1ea) CASEMBC(0x1ec) CASEMBC(0x1ece)
-		      regmbc('O'); regmbc('\322'); regmbc('\323');
-		      regmbc('\324'); regmbc('\325'); regmbc('\326');
-		      regmbc('\330');
+		      regmbc('O'); regmbc(0xd2); regmbc(0xd3);
+		      regmbc(0xd4); regmbc(0xd5); regmbc(0xd6);
+		      regmbc(0xd8);
 		      REGMBC(0x14c) REGMBC(0x14e) REGMBC(0x150)
 		      REGMBC(0x1a0) REGMBC(0x1d1) REGMBC(0x1ea)
 		      REGMBC(0x1ec) REGMBC(0x1ece)
@@ -956,12 +957,12 @@
 		      regmbc('T'); REGMBC(0x162) REGMBC(0x164)
 		      REGMBC(0x166) REGMBC(0x1e6a) REGMBC(0x1e6e)
 		      return;
-	    case 'U': case '\331': case '\332': case '\333': case '\334':
+	    case 'U': case 0xd9: case 0xda: case 0xdb: case 0xdc:
 	    CASEMBC(0x168) CASEMBC(0x16a) CASEMBC(0x16c) CASEMBC(0x16e)
 	    CASEMBC(0x170) CASEMBC(0x172) CASEMBC(0x1af) CASEMBC(0x1d3)
 	    CASEMBC(0x1ee6)
-		      regmbc('U'); regmbc('\331'); regmbc('\332');
-		      regmbc('\333'); regmbc('\334');
+		      regmbc('U'); regmbc(0xd9); regmbc(0xda);
+		      regmbc(0xdb); regmbc(0xdc);
 		      REGMBC(0x168) REGMBC(0x16a) REGMBC(0x16c)
 		      REGMBC(0x16e) REGMBC(0x170) REGMBC(0x172)
 		      REGMBC(0x1af) REGMBC(0x1d3) REGMBC(0x1ee6)
@@ -977,10 +978,10 @@
 	    case 'X': CASEMBC(0x1e8a) CASEMBC(0x1e8c)
 		      regmbc('X'); REGMBC(0x1e8a) REGMBC(0x1e8c)
 		      return;
-	    case 'Y': case '\335':
+	    case 'Y': case 0xdd:
 	    CASEMBC(0x176) CASEMBC(0x178) CASEMBC(0x1e8e) CASEMBC(0x1ef2)
 	    CASEMBC(0x1ef6) CASEMBC(0x1ef8)
-		      regmbc('Y'); regmbc('\335');
+		      regmbc('Y'); regmbc(0xdd);
 		      REGMBC(0x176) REGMBC(0x178) REGMBC(0x1e8e)
 		      REGMBC(0x1ef2) REGMBC(0x1ef6) REGMBC(0x1ef8)
 		      return;
@@ -990,13 +991,13 @@
 		      REGMBC(0x17d) REGMBC(0x1b5) REGMBC(0x1e90)
 		      REGMBC(0x1e94)
 		      return;
-	    case 'a': case '\340': case '\341': case '\342':
-	    case '\343': case '\344': case '\345':
+	    case 'a': case 0xe0: case 0xe1: case 0xe2:
+	    case 0xe3: case 0xe4: case 0xe5:
 	    CASEMBC(0x101) CASEMBC(0x103) CASEMBC(0x105) CASEMBC(0x1ce)
 	    CASEMBC(0x1df) CASEMBC(0x1e1) CASEMBC(0x1ea3)
-		      regmbc('a'); regmbc('\340'); regmbc('\341');
-		      regmbc('\342'); regmbc('\343'); regmbc('\344');
-		      regmbc('\345');
+		      regmbc('a'); regmbc(0xe0); regmbc(0xe1);
+		      regmbc(0xe2); regmbc(0xe3); regmbc(0xe4);
+		      regmbc(0xe5);
 		      REGMBC(0x101) REGMBC(0x103) REGMBC(0x105)
 		      REGMBC(0x1ce) REGMBC(0x1df) REGMBC(0x1e1)
 		      REGMBC(0x1ea3)
@@ -1004,9 +1005,9 @@
 	    case 'b': CASEMBC(0x1e03) CASEMBC(0x1e07)
 		      regmbc('b'); REGMBC(0x1e03) REGMBC(0x1e07)
 		      return;
-	    case 'c': case '\347':
+	    case 'c': case 0xe7:
 	    CASEMBC(0x107) CASEMBC(0x109) CASEMBC(0x10b) CASEMBC(0x10d)
-		      regmbc('c'); regmbc('\347');
+		      regmbc('c'); regmbc(0xe7);
 		      REGMBC(0x107) REGMBC(0x109) REGMBC(0x10b)
 		      REGMBC(0x10d)
 		      return;
@@ -1015,11 +1016,11 @@
 		      regmbc('d'); REGMBC(0x10f) REGMBC(0x111)
 		      REGMBC(0x1e0b) REGMBC(0x01e0f) REGMBC(0x1e11)
 		      return;
-	    case 'e': case '\350': case '\351': case '\352': case '\353':
+	    case 'e': case 0xe8: case 0xe9: case 0xea: case 0xeb:
 	    CASEMBC(0x113) CASEMBC(0x115) CASEMBC(0x117) CASEMBC(0x119)
 	    CASEMBC(0x11b) CASEMBC(0x1ebb) CASEMBC(0x1ebd)
-		      regmbc('e'); regmbc('\350'); regmbc('\351');
-		      regmbc('\352'); regmbc('\353');
+		      regmbc('e'); regmbc(0xe8); regmbc(0xe9);
+		      regmbc(0xea); regmbc(0xeb);
 		      REGMBC(0x113) REGMBC(0x115) REGMBC(0x117)
 		      REGMBC(0x119) REGMBC(0x11b) REGMBC(0x1ebb)
 		      REGMBC(0x1ebd)
@@ -1040,11 +1041,11 @@
 		      REGMBC(0x1e23) REGMBC(0x1e27) REGMBC(0x1e29)
 		      REGMBC(0x1e96)
 		      return;
-	    case 'i': case '\354': case '\355': case '\356': case '\357':
+	    case 'i': case 0xec: case 0xed: case 0xee: case 0xef:
 	    CASEMBC(0x129) CASEMBC(0x12b) CASEMBC(0x12d) CASEMBC(0x12f)
 	    CASEMBC(0x1d0) CASEMBC(0x1ec9)
-		      regmbc('i'); regmbc('\354'); regmbc('\355');
-		      regmbc('\356'); regmbc('\357');
+		      regmbc('i'); regmbc(0xec); regmbc(0xed);
+		      regmbc(0xee); regmbc(0xef);
 		      REGMBC(0x129) REGMBC(0x12b) REGMBC(0x12d)
 		      REGMBC(0x12f) REGMBC(0x1d0) REGMBC(0x1ec9)
 		      return;
@@ -1065,20 +1066,20 @@
 	    case 'm': CASEMBC(0x1e3f) CASEMBC(0x1e41)
 		      regmbc('m'); REGMBC(0x1e3f) REGMBC(0x1e41)
 		      return;
-	    case 'n': case '\361':
+	    case 'n': case 0xf1:
 	    CASEMBC(0x144) CASEMBC(0x146) CASEMBC(0x148) CASEMBC(0x149)
 	    CASEMBC(0x1e45) CASEMBC(0x1e49)
-		      regmbc('n'); regmbc('\361');
+		      regmbc('n'); regmbc(0xf1);
 		      REGMBC(0x144) REGMBC(0x146) REGMBC(0x148)
 		      REGMBC(0x149) REGMBC(0x1e45) REGMBC(0x1e49)
 		      return;
-	    case 'o': case '\362': case '\363': case '\364': case '\365':
-	    case '\366': case '\370':
+	    case 'o': case 0xf2: case 0xf3: case 0xf4: case 0xf5:
+	    case 0xf6: case 0xf8:
 	    CASEMBC(0x14d) CASEMBC(0x14f) CASEMBC(0x151) CASEMBC(0x1a1)
 	    CASEMBC(0x1d2) CASEMBC(0x1eb) CASEMBC(0x1ed) CASEMBC(0x1ecf)
-		      regmbc('o'); regmbc('\362'); regmbc('\363');
-		      regmbc('\364'); regmbc('\365'); regmbc('\366');
-		      regmbc('\370');
+		      regmbc('o'); regmbc(0xf2); regmbc(0xf3);
+		      regmbc(0xf4); regmbc(0xf5); regmbc(0xf6);
+		      regmbc(0xf8);
 		      REGMBC(0x14d) REGMBC(0x14f) REGMBC(0x151)
 		      REGMBC(0x1a1) REGMBC(0x1d2) REGMBC(0x1eb)
 		      REGMBC(0x1ed) REGMBC(0x1ecf)
@@ -1101,12 +1102,12 @@
 		      regmbc('t'); REGMBC(0x163) REGMBC(0x165) REGMBC(0x167)
 		      REGMBC(0x1e6b) REGMBC(0x1e6f) REGMBC(0x1e97)
 		      return;
-	    case 'u': case '\371': case '\372': case '\373': case '\374':
+	    case 'u': case 0xf9: case 0xfa: case 0xfb: case 0xfc:
 	    CASEMBC(0x169) CASEMBC(0x16b) CASEMBC(0x16d) CASEMBC(0x16f)
 	    CASEMBC(0x171) CASEMBC(0x173) CASEMBC(0x1b0) CASEMBC(0x1d4)
 	    CASEMBC(0x1ee7)
-		      regmbc('u'); regmbc('\371'); regmbc('\372');
-		      regmbc('\373'); regmbc('\374');
+		      regmbc('u'); regmbc(0xf9); regmbc(0xfa);
+		      regmbc(0xfb); regmbc(0xfc);
 		      REGMBC(0x169) REGMBC(0x16b) REGMBC(0x16d)
 		      REGMBC(0x16f) REGMBC(0x171) REGMBC(0x173)
 		      REGMBC(0x1b0) REGMBC(0x1d4) REGMBC(0x1ee7)
@@ -1123,10 +1124,10 @@
 	    case 'x': CASEMBC(0x1e8b) CASEMBC(0x1e8d)
 		      regmbc('x'); REGMBC(0x1e8b) REGMBC(0x1e8d)
 		      return;
-	    case 'y': case '\375': case '\377':
+	    case 'y': case 0xfd: case 0xff:
 	    CASEMBC(0x177) CASEMBC(0x1e8f) CASEMBC(0x1e99)
 	    CASEMBC(0x1ef3) CASEMBC(0x1ef7) CASEMBC(0x1ef9)
-		      regmbc('y'); regmbc('\375'); regmbc('\377');
+		      regmbc('y'); regmbc(0xfd); regmbc(0xff);
 		      REGMBC(0x177) REGMBC(0x1e8f) REGMBC(0x1e99)
 		      REGMBC(0x1ef3) REGMBC(0x1ef7) REGMBC(0x1ef9)
 		      return;
diff --git a/src/testdir/test44.in b/src/testdir/test44.in
index 69fbb94..23bb4f8 100644
--- a/src/testdir/test44.in
+++ b/src/testdir/test44.in
@@ -24,17 +24,25 @@
 x:" find word by change of word class
 /ち\<カヨ\>は
 x:" Test \%u, [\u] and friends
+:" c
 /\%u20ac
-x/[\u4f7f\u5929]\+
-x/\%U12345678
-x/[\U1234abcd\u1234\uabcd]
-x/\%d21879b
-x/ [[=A=]]* [[=B=]]* [[=C=]]* [[=D=]]* [[=E=]]* [[=F=]]* [[=G=]]* [[=H=]]* [[=I=]]* [[=J=]]* [[=K=]]* [[=L=]]* [[=M=]]* [[=N=]]* [[=O=]]* [[=P=]]* [[=Q=]]* [[=R=]]* [[=S=]]* [[=T=]]* [[=U=]]* [[=V=]]* [[=W=]]* [[=X=]]* [[=Y=]]* [[=Z=]]*/e
-x/ [[=a=]]* [[=b=]]* [[=c=]]* [[=d=]]* [[=e=]]* [[=f=]]* [[=g=]]* [[=h=]]* [[=i=]]* [[=j=]]* [[=k=]]* [[=l=]]* [[=m=]]* [[=n=]]* [[=o=]]* [[=p=]]* [[=q=]]* [[=r=]]* [[=s=]]* [[=t=]]* [[=u=]]* [[=v=]]* [[=w=]]* [[=x=]]* [[=y=]]* [[=z=]]*/e
-x:" Test backwards search from a multi-byte char
+x:" d
+/[\u4f7f\u5929]\+
+x:" e
+/\%U12345678
+x:" f
+/[\U1234abcd\u1234\uabcd]
+x:" g
+/\%d21879b
+x:" h
+/ [[=A=]]* [[=B=]]* [[=C=]]* [[=D=]]* [[=E=]]* [[=F=]]* [[=G=]]* [[=H=]]* [[=I=]]* [[=J=]]* [[=K=]]* [[=L=]]* [[=M=]]* [[=N=]]* [[=O=]]* [[=P=]]* [[=Q=]]* [[=R=]]* [[=S=]]* [[=T=]]* [[=U=]]* [[=V=]]* [[=W=]]* [[=X=]]* [[=Y=]]* [[=Z=]]*/e
+x:" i
+/ [[=a=]]* [[=b=]]* [[=c=]]* [[=d=]]* [[=e=]]* [[=f=]]* [[=g=]]* [[=h=]]* [[=i=]]* [[=j=]]* [[=k=]]* [[=l=]]* [[=m=]]* [[=n=]]* [[=o=]]* [[=p=]]* [[=q=]]* [[=r=]]* [[=s=]]* [[=t=]]* [[=u=]]* [[=v=]]* [[=w=]]* [[=x=]]* [[=y=]]* [[=z=]]*/e
+x:" j Test backwards search from a multi-byte char
 /x
 x?.
-x:let @w=':%s#comb[i]nations#œ̄ṣ́m̥̄ᾱ̆́#g'
+x:" k
+:let @w=':%s#comb[i]nations#œ̄ṣ́m̥̄ᾱ̆́#g'
 :@w
 :?^1?,$w! test.out
 :e! test.out
diff --git a/src/version.c b/src/version.c
index d211340..11dd808 100644
--- a/src/version.c
+++ b/src/version.c
@@ -742,6 +742,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    704,
+/**/
     703,
 /**/
     702,