dash vs. bash inconsistency

[Thomas Wolff]

Am 28.03.2020 um 02:09 schrieb Sasha Slijepcevic via Cygwin:
> I am using Cygwin 3.1.4-1, bash 4.4.12-3 and dash 0.5.9.1-1.
>
> I have a setup.exe in the root of my Cygwin installation, C:\cygwin64, for example.
> If I set PATH=C:\cygwin64;C:\cygwin64\bin, I can run setup.exe from bash.
>
> C:\>set PATH=C:\cygwin64;C:\cygwin64\bin
>
> C:\>bash
> $ echo $PATH
> /:/usr/bin
> $ setup-x86_64.exe  --version
> Cygwin setup 2.903
>
> However, in dash:
> C:\>dash
> $ echo $PATH
> /:/usr/bin
> $ setup-x86-64.exe --version
> dash: 2: setup-x86-64.exe: not found
>
> Am I misusing Cygwin trying to run executables from the top of the installation? Is it expected to all shells would behave the same?
Do you happen to have placed a copy of dash into your assumed root, 
C:\cygwin64\dash.exe?