[PATCH] ld/PE: restrict non-zero default DLL characteristics to MinGW

[Jeremy Drake]

On Fri, 4 Apr 2025, Jan Beulich wrote:

> While commit ef6379e16dd1 ("Set the default DLL chracteristics to 0 for
> Cygwin based targets") tried to undo the too broad earlier 514b4e191d5f
> ("Change the default characteristics of DLLs built by the linker to more
> secure settings"), it didn't go quite far enough. Apparently the
> assumption was that if it's not MinGW, it must be Cygwin. Whether it
> really is okay to default three of the flags to non-zero on MinGW also
> remains unclear - sadly neither of the commits came with any description
> whatsoever.

A bit of history on 514b4e191d5f is that I posted a patch on bugzilla on a
years-old bug requesting these flags changes, and was surprised that it
was applied so quickly.  I didn't write the commit message.