Re: [PATCH 2/2] mingw: enable DEP and ASLR

From: Jeff King <peff@peff.net>
Date: May 1, 2019, 20:46 UTC
Message-ID: <20190501204631.GB13372@sigill.intra.peff.net>
In-Reply-To: <nycvar.QRO.7.76.6.1904301838400.45@tvgsbejvaqbjf.bet>

On Tue, Apr 30, 2019 at 06:41:29PM -0400, Johannes Schindelin wrote:

Show 11 quoted lines

> > I'm a bit concerned that this breaks my debug sessions where I use -O0.
> > But I'll test without -O0 before I really complain.
> 
> Weird. Jameson Miller also mentioned this very concern in an internal
> review.
> 
> I guess I'll do something like
> 
> 	ifneq (,$(findstring -O,$(filter-out -O0,$(CFLAGS))))
> 
> Does that work for you?

I wonder if this points to this patch touching the wrong level. These compiler flags are a thing that _some_ builds want (i.e., production builds where people care most about security and not about debugging), but not necessarily all.

I'd have expected this to be tweakable by a Makefile knob (either a specific knob, or just the caller setting the right CFLAGS etc), and then for the builds of Git for Windows to turn those knobs when making a package to distribute.

Our internal package builds at GitHub all have this in their config.mak (for Linux, of course):

  CFLAGS += -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=1
  CFLAGS += -fstack-protector-strong

  CFLAGS += -fpie
  LDFLAGS += -z relro -z now
  LDFLAGS += -pie

and I wouldn't be surprised if other binary distributors (like the Debian package) do something similar.

-Peff