$HOME does not get abbreviated in prompt \w output when there is a trailing slash

[Libor Pechacek]

Configuration Information [Automatically generated, do not change]:
Machine: x86_64
OS: linux-gnu
Compiler: gcc -I/home/abuild/rpmbuild/BUILD/bash-4.2 
-L/home/abuild/rpmbuild/BUILD/bash-4.2/../readline-6.2
Compilation CFLAGS:  -DPROGRAM='bash' -DCONF_HOSTTYPE='x86_64' 
-DCONF_OSTYPE='linux-gnu' -DCONF_MACHTYPE='x86_64-suse-linux-gnu' 
-DCONF_VENDOR='suse' -DLOCALEDIR='/usr/share/locale' -DPACKAGE='bash' -DSHELL 
-DHAVE_CONFIG_H   -I.  -I. -I./include -I./lib   -fmessage-length=0 
-grecord-gcc-switches -fstack-protector -O2 -Wall -D_FORTIFY_SOURCE=2 
-funwind-tables -fasynchronous-unwind-tables -g  -D_GNU_SOURCE -DRECYCLES_PIDS 
-Wall -g -std=gnu89 -Wuninitialized -Wextra -Wno-unprototyped-calls 
-Wno-switch-enum -Wno-unused-variable -Wno-unused-parameter -ftree-loop-linear 
-pipe -DBNC382214=0 -fprofile-use
uname output: Linux fmn.suse.cz 3.12.18-4-default #1 SMP Thu May 8 16:21:49 UTC 
2014 (607beab) x86_64 x86_64 x86_64 GNU/Linux
Machine Type: x86_64-suse-linux-gnu

Bash Version: 4.2
Patch Level: 46
Release Status: release

Description:
        Bash prompt always shows full path in prompt instead of tilde
        abbreviation when $HOME ends with slash.

Repeat-By:
        lpechacek@fmn:~> PS1='\w\$ '
        ~$ HOME=/home/lpechacek/
        /home/lpechacek$ HOME=/home/lpechacek
        ~$  # the above line should start with '~$ '