[BUG] Directory probing for aliases

Hi, Git aliases stop working when user doesn't have permissions to any directory within $PATH list:

% git config alias.br branch % git br fatal: cannot exec 'git-br': Permission denied

Problem seems to be in directories probing:

execve("/usr/libexec/git-core/git-br", ["git-br"], [/* 76 vars */]) = -1 ENOENT (No such file or directory) execve("/home/vayerx/bin/git-br", ["git-br"], [/* 76 vars */]) = -1 ENOENT (No such file or directory) execve("/usr/local/bin/git-br", ["git-br"], [/* 76 vars */]) = -1 ENOENT (No such file or directory) execve("/usr/bin/git-br", ["git-br"], [/* 76 vars */]) = -1 ENOENT (No such file or directory) execve("/bin/git-br", ["git-br"], [/* 76 vars */]) = -1 ENOENT (No such file or directory) execve("/opt/bin/git-br", ["git-br"], [/* 76 vars */]) = -1 ENOENT (No such file or directory) execve("/usr/x86_64-pc-linux-gnu/gcc-bin/4.6.3/git-br", ["git-br"], [/* 76 vars */]) = -1 ENOENT (No such file or directory) execve("/usr/games/bin/git-br", ["git-br"], [/* 76 vars */]) = -1 EACCES (Permission denied) write(2, "fatal: ", 7fatal: ) = 7 write(2, "cannot exec 'git-br': Permission"..., 39cannot exec 'git-br': Permission denied) = 39

(user doesn't have access to '/usr/games/bin' directory) Everything works fine if '/usr/games/bin' is not listed in $PATH variable. Standard/built-in git commands work fine regardless of $PATH variable.