diff --git a/client/mysqldump.c b/client/mysqldump.c
index 1e0f68eb94e..49bc56890fb 100644
--- a/client/mysqldump.c
+++ b/client/mysqldump.c
@@ -1480,7 +1480,7 @@ static ulong find_set(TYPELIB *lib, const char *x, uint length,
   uint find;
   char buff[255];
 
-  *err_pos= 0;                  // No error yet
+  *err_pos= 0;                  /* No error yet */
   while (end > x && my_isspace(system_charset_info, end[-1]))
     end--;
 
diff --git a/client/mysqlshow.c b/client/mysqlshow.c
index e6e21f177ef..9b376872ff8 100644
--- a/client/mysqlshow.c
+++ b/client/mysqlshow.c
@@ -89,7 +89,7 @@ int main(int argc, char **argv)
       }
       *to= *pos;
     }    
-    *to= *pos; // just to copy a '\0'  if '\\' was used
+    *to= *pos; /* just to copy a '\0'  if '\\' was used */
   }
   if (first_argument_uses_wildcards)
     wild= argv[--argc];
diff --git a/strings/ctype-bin.c b/strings/ctype-bin.c
index e7c3a941109..b39697e6f81 100644
--- a/strings/ctype-bin.c
+++ b/strings/ctype-bin.c
@@ -200,7 +200,7 @@ static int my_wildcmp_bin(CHARSET_INFO *cs,
 			   const char *wildstr,const char *wildend,
 			   int escape, int w_one, int w_many)
 {
-  int result= -1;				// Not found, using wildcards
+  int result= -1;				/* Not found, using wildcards */
   
   while (wildstr != wildend)
   {
@@ -214,15 +214,15 @@ static int my_wildcmp_bin(CHARSET_INFO *cs,
       }
       if (wildstr == wildend)
       {
-	return(str != str_end);			// Match if both are at end
+	return(str != str_end);			/* Match if both are at end */
       }
-      result=1;					// Found an anchor char
+      result=1;					/* Found an anchor char */
     }
     if (*wildstr == w_one)
     {
       do
       {
-	if (str == str_end)			// Skip one char if possible
+	if (str == str_end)			/* Skip one char if possible */
 	  return(result);
 	str++;
       } while (*++wildstr == w_one && wildstr != wildend);
@@ -230,7 +230,7 @@ static int my_wildcmp_bin(CHARSET_INFO *cs,
 	break;
     }
     if (*wildstr == w_many)
-    {						// Found w_many
+    {						/* Found w_many */
       char cmp;
       
       wildstr++;
@@ -248,11 +248,11 @@ static int my_wildcmp_bin(CHARSET_INFO *cs,
 	  str++;
 	  continue;
 	}
-	break;					// Not a wild character
+	break;					/* Not a wild character */
       }
       if (wildstr == wildend)
       {
-	return(0);				// Ok if w_many is last
+	return(0);				/* Ok if w_many is last */
       }
       if (str == str_end)
       {
@@ -261,7 +261,7 @@ static int my_wildcmp_bin(CHARSET_INFO *cs,
       
       if ((cmp= *wildstr) == escape && wildstr+1 != wildend)
 	cmp= *++wildstr;
-      wildstr++;				// This is compared trough cmp
+      wildstr++;				/* This is compared trough cmp */
       do
       {
 	while (str != str_end && *str != cmp)
diff --git a/strings/ctype-mb.c b/strings/ctype-mb.c
index aa4ccdb6af7..4c1f791b8e4 100644
--- a/strings/ctype-mb.c
+++ b/strings/ctype-mb.c
@@ -161,7 +161,7 @@ int my_wildcmp_mb(CHARSET_INFO *cs,
 		  const char *wildstr,const char *wildend,
 		  int escape, int w_one, int w_many)
 {
-  int result= -1;				// Not found, using wildcards
+  int result= -1;				/* Not found, using wildcards */
 
   bool use_mb_flag=use_mb(cs);
 
@@ -182,16 +182,16 @@ int my_wildcmp_mb(CHARSET_INFO *cs,
       }
       else
       if (str == str_end || likeconv(cs,*wildstr++) != likeconv(cs,*str++))
-	return(1);				// No match
+	return(1);				/* No match */
       if (wildstr == wildend)
-	return (str != str_end);		// Match if both are at end
-      result=1;					// Found an anchor char
+	return (str != str_end);		/* Match if both are at end */
+      result=1;					/* Found an anchor char */
     }
     if (*wildstr == w_one)
     {
       do
       {
-	if (str == str_end)			// Skip one char if possible
+	if (str == str_end)			/* Skip one char if possible */
 	  return (result);
 	INC_PTR(cs,str,str_end);
       } while (++wildstr < wildend && *wildstr == w_one);
@@ -199,7 +199,7 @@ int my_wildcmp_mb(CHARSET_INFO *cs,
 	break;
     }
     if (*wildstr == w_many)
-    {						// Found w_many
+    {						/* Found w_many */
       uchar cmp;
       const char* mb = wildstr;
       int mblen=0;
@@ -217,10 +217,10 @@ int my_wildcmp_mb(CHARSET_INFO *cs,
 	  INC_PTR(cs,str,str_end);
 	  continue;
 	}
-	break;					// Not a wild character
+	break;					/* Not a wild character */
       }
       if (wildstr == wildend)
-	return(0);				// Ok if w_many is last
+	return(0);				/* Ok if w_many is last */
       if (str == str_end)
 	return -1;
       
@@ -231,7 +231,7 @@ int my_wildcmp_mb(CHARSET_INFO *cs,
       LINT_INIT(mblen);
       if (use_mb_flag)
         mblen = my_ismbchar(cs, wildstr, wildend);
-      INC_PTR(cs,wildstr,wildend);		// This is compared trough cmp
+      INC_PTR(cs,wildstr,wildend);		/* This is compared trough cmp */
       cmp=likeconv(cs,cmp);   
       do
       {
diff --git a/strings/t_ctype.h b/strings/t_ctype.h
index ac1fa408c0e..4f6f78cd188 100644
--- a/strings/t_ctype.h
+++ b/strings/t_ctype.h
@@ -40,7 +40,7 @@ typedef unsigned char tchar;
 #define IGNORE 0
 
 
-// level 1 symbols & order
+/* level 1 symbols & order */
 enum l1_symbols {
     L1_08 = TOT_LEVELS,
     L1_18,
@@ -142,7 +142,7 @@ enum l1_symbols {
     L1_SARA_AI_MAIMALAI
 };
 
-// level 2 symbols & order
+/* level 2 symbols & order */
 enum l2_symbols {
     L2_BLANK = TOT_LEVELS,
     L2_THAII,
@@ -156,7 +156,7 @@ enum l2_symbols {
     L2_TONE4
 };
 
-// level 3 symbols & order
+/* level 3 symbols & order */
 enum l3_symbols {
 	L3_BLANK = TOT_LEVELS,
     L3_SPACE,
@@ -201,7 +201,7 @@ enum l3_symbols {
     L3_V_LINE
 };
 
-// level 4 symbols & order
+/* level 4 symbols & order */
 enum l4_symbols {
     L4_BLANK = TOT_LEVELS,
     L4_MIN,