On Mon, Mar 13, 2017 at 09:47:54PM +0100, Marc Stevens wrote: > Linus: > I would be surprised, the dependencies should be automatically determined. > > BTW Did you make local changes to this perf branch? I can reproduce it with: cd sha1collisiondetection git clean -dqfx ;# make sure we are starting from scratch git checkout 9c8e73cadb35776d3310e3f8ceda7183fa75a39f make bin/sha1dcsum $file git checkout 55d1db0980501e582f6cd103a04f493995b1df78 make bin/sha1dcsum $file The final call to sha1dcsum will report a collision, even though the first one did not. It also reproduces with the original snippet I posted. I didn't notice because I was just collecting the timings then (and I originally noticed the problem on the versions I had pulled into Git, where it works as expected; but then I am just pulling in the two source files, without all of the libtool magic). -Peff