BASH PATCH REPORT
			     =================

Bash-Release:	5.3
Patch-ID:	bash53-019

Bug-Reported-by:	zheng <charname@qq.com>
Bug-Reference-ID:	<tencent_19D6EE3366FEA3EF2C5FD6C23DF303156D09@qq.com>
Bug-Reference-URL:	https://lists.gnu.org/archive/html/bug-bash/2026-08/msg00010.html

Bug-Description:

On some systems, macOS in particular, isalpha(3) returns true for bytes
between 128 and 255. Bash uses this to determine whether or not these
characters are permitted to be part of a shell identifier, and can
consume one byte too many when determining the end of a variable name.

Patch (apply with `patch -p0'):

*** ../bash-5.3-patched/syntax.h	Mon Sep 14 10:20:05 2020
--- syntax.h	Thu Aug  6 14:11:25 2026
***************
*** 64,67 ****
--- 64,69 ----
  #define CSUBSTOP	0x1000	/* values of OP for ${word[:]OPstuff} */
  #define CBLANK		0x2000	/* whitespace (blank) character */
+ #define CNAME		0x4000	/* POSIX name character ([_0-9a-zA-Z]) */
+ #define CNAMESTART	0x8000	/* POSIX name start character ([_a-zA-Z]) */
  
  /* Defines for use by the rest of the shell. */
*** ../bash-5.3-patched/mksyntax.c	Thu May 16 15:35:55 2024
--- mksyntax.c	Wed Aug  5 15:27:45 2026
***************
*** 61,64 ****
--- 61,66 ----
  	{ CSUBSTOP,	"CSUBSTOP" },
  	{ CBLANK,	"CBLANK" },
+ 	{ CNAME,	"CNAME" },
+ 	{ CNAMESTART,	"CNAMESTART" }
  };
  	
***************
*** 199,202 ****
--- 201,243 ----
  }
  
+ static void
+ setnamechars(void)
+ {
+   lsyntax['_'] |= CNAME|CNAMESTART;
+ 
+   lsyntax['0'] |= CNAME; lsyntax['1'] |= CNAME; lsyntax['2'] |= CNAME;
+   lsyntax['3'] |= CNAME; lsyntax['4'] |= CNAME; lsyntax['5'] |= CNAME;
+   lsyntax['6'] |= CNAME; lsyntax['7'] |= CNAME; lsyntax['8'] |= CNAME;
+   lsyntax['9'] |= CNAME;
+ 
+   lsyntax['a'] |= CNAME|CNAMESTART; lsyntax['b'] |= CNAME|CNAMESTART;
+   lsyntax['c'] |= CNAME|CNAMESTART; lsyntax['d'] |= CNAME|CNAMESTART;
+   lsyntax['e'] |= CNAME|CNAMESTART; lsyntax['f'] |= CNAME|CNAMESTART;
+   lsyntax['g'] |= CNAME|CNAMESTART; lsyntax['h'] |= CNAME|CNAMESTART;
+   lsyntax['i'] |= CNAME|CNAMESTART; lsyntax['j'] |= CNAME|CNAMESTART;
+   lsyntax['k'] |= CNAME|CNAMESTART; lsyntax['l'] |= CNAME|CNAMESTART;
+   lsyntax['m'] |= CNAME|CNAMESTART; lsyntax['n'] |= CNAME|CNAMESTART;
+   lsyntax['o'] |= CNAME|CNAMESTART; lsyntax['p'] |= CNAME|CNAMESTART;
+   lsyntax['q'] |= CNAME|CNAMESTART; lsyntax['r'] |= CNAME|CNAMESTART;
+   lsyntax['s'] |= CNAME|CNAMESTART; lsyntax['t'] |= CNAME|CNAMESTART;
+   lsyntax['u'] |= CNAME|CNAMESTART; lsyntax['v'] |= CNAME|CNAMESTART;
+   lsyntax['w'] |= CNAME|CNAMESTART; lsyntax['x'] |= CNAME|CNAMESTART;
+   lsyntax['y'] |= CNAME|CNAMESTART; lsyntax['z'] |= CNAME|CNAMESTART;
+ 
+   lsyntax['A'] |= CNAME|CNAMESTART; lsyntax['B'] |= CNAME|CNAMESTART;
+   lsyntax['C'] |= CNAME|CNAMESTART; lsyntax['D'] |= CNAME|CNAMESTART;
+   lsyntax['E'] |= CNAME|CNAMESTART; lsyntax['F'] |= CNAME|CNAMESTART;
+   lsyntax['G'] |= CNAME|CNAMESTART; lsyntax['H'] |= CNAME|CNAMESTART;
+   lsyntax['I'] |= CNAME|CNAMESTART; lsyntax['J'] |= CNAME|CNAMESTART;
+   lsyntax['K'] |= CNAME|CNAMESTART; lsyntax['L'] |= CNAME|CNAMESTART;
+   lsyntax['M'] |= CNAME|CNAMESTART; lsyntax['N'] |= CNAME|CNAMESTART;
+   lsyntax['O'] |= CNAME|CNAMESTART; lsyntax['P'] |= CNAME|CNAMESTART;
+   lsyntax['Q'] |= CNAME|CNAMESTART; lsyntax['R'] |= CNAME|CNAMESTART;
+   lsyntax['S'] |= CNAME|CNAMESTART; lsyntax['T'] |= CNAME|CNAMESTART;
+   lsyntax['U'] |= CNAME|CNAMESTART; lsyntax['V'] |= CNAME|CNAMESTART;
+   lsyntax['W'] |= CNAME|CNAMESTART; lsyntax['X'] |= CNAME|CNAMESTART;
+   lsyntax['Y'] |= CNAME|CNAMESTART; lsyntax['Z'] |= CNAME|CNAMESTART;
+ }
+ 
  /* load up the correct flag values in lsyntax */
  static void
***************
*** 235,238 ****
--- 276,281 ----
  
    addblanks ();
+ 
+   setnamechars ();
  }
  
*** ../bash-5.3-patched/general.h	Tue Jul  7 11:13:48 2026
--- general.h	Thu Aug  6 14:07:22 2026
***************
*** 111,116 ****
  
  /* Define exactly what a legal shell identifier consists of. */
! #define legal_variable_starter(c) (ISALPHA(c) || (c == '_'))
! #define legal_variable_char(c)	(ISALNUM(c) || c == '_')
  
  /* Definitions used in subst.c and by the `read' builtin for field
--- 111,121 ----
  
  /* Define exactly what a legal shell identifier consists of. */
! #if 0
! #define legal_variable_starter(c) (c < 128 && (ISALPHA(c) || c == '_'))
! #define legal_variable_char(c)	(c < 128 && (ISALNUM(c) || c == '_'))
! #else
! #define legal_variable_starter(c) (sh_syntaxtab[c] & CNAMESTART)
! #define legal_variable_char(c)	(sh_syntaxtab[c] & CNAME)
! #endif
  
  /* Definitions used in subst.c and by the `read' builtin for field
*** ../bash-5.3/patchlevel.h	2020-06-22 14:51:03.000000000 -0400
--- patchlevel.h	2020-10-01 11:01:28.000000000 -0400
***************
*** 26,30 ****
     looks for to find the patch level (for the sccs version string). */
  
! #define PATCHLEVEL 18
  
  #endif /* _PATCHLEVEL_H_ */
--- 26,30 ----
     looks for to find the patch level (for the sccs version string). */
  
! #define PATCHLEVEL 19
  
  #endif /* _PATCHLEVEL_H_ */