${parameter#[:upper:]} does not work with LANG=en_US

[Jim Avera]

Configuration Information [Automatically generated, do not change]:
Machine: i386
OS: Linux
Compiler: gcc
Compilation CFLAGS:   -DHAVE_VFPRINTF -DHAVE_UNISTD_H -DHAVE_STDLIB_H 
-DHAVE_LIMITS_H        -DHAVE_GETGROUPS -DHAVE_RESOURCE -DHAVE_SYS_PARAM 
-DVOID_SIGHANDLER -DHAVE_GETDTABLESIZE -DHAVE_BCOPY -DHAVE_GETPW_DECLS 
-DHAVE_GETHOSTNAME -DHAVE_WAIT_H         -DHAVE_DUP2 -DHAVE_STRERROR  
-DHAVE_DIRENT_H -DHAVE_STRING_H        -DHAVE_VARARGS_H -DHAVE_STRCHR  
-DHAVE_DEV_FD        -Di386 -DLinux -DSHELL -DHAVE_ALLOCA -DHAVE_ALLOCA_H       
-O2 -m486 -fno-strength-reduce
uname output: Linux red3 2.4.2 #2 SMP Wed Apr 25 01:26:59 PDT 2001 i686 unknown

Bash Version: 1.14
Patch Level: 7

Description:
        The POSIX.2 character class [:upper:] does not work in the
        ${param#[...]} syntax.  The [:upper:] pattern does not match 
        an an initial upper-case letter.

        Note, however, that ${param%...} *does* seem to work (see demo).

        This was observed when no env vars other than PATH are set:

Repeat-By:
        Run this demo script.
        You can do env - PATH=/bin:/usr/bin scriptfile
        to avoid influences from environment variables I didn't have.

                #!/bin/bash
                foo="Atail"
                
                tr_result=`echo $foo | tr '[:upper:]' '[:lower:]'`
                if test "X$tr_result" != "Xatail" ; then
                    echo "TEST FAILED: tr with POSIX.2 char classes"
                    echo "Got '$tr_result' expected 'atail'"
                fi
                
                res1="${foo#[A-Z]}"
                if test "X$res1" != "Xtail" ; then
                    echo "TEST FAILED: \${foo#[A-Z]}"
                    echo "Got '$res1' expected 'tail'"
                fi
                
                res2="${foo#[:upper:]}"
        ### THIS ONE FAILS ###
                if test "X$res2" != "Xtail" ; then
                    echo "TEST FAILED: \${foo#[:upper:]}"
                    echo "Got '$res2' expected 'tail'"
                fi
                
                res3="${foo%[a-z]}"
                if test "X$res3" != "XAtai" ; then
                    echo "TEST FAILED: \${foo%[a-z]}"
                    echo "Got '$res3' expected 'Atai'"
                fi
                
                res4="${foo%[:lower:]}"
                if test "X$res4" != "XAtai" ; then
                    echo "TEST FAILED: \${foo%[:lower:]}"
                    echo "Got '$res4' expected 'Atai'"
                fi
        #---------- end of demo script ---------