bug#37974: eww produces "error in process filter: Specified time is not representable"

[Stuart Little]

I believe I've isolated this as far as I can: the systems running Emacs 26.1 
and 26.3 respectively have identical code for the function 
'url-cookie-handle-set-cookie', so that on its own is not the problem. Rather, 
'format-time-string' works fine on the x86_64 Arch Linux system but not the 
Debian i686:

On the former, evaluating

(format-time-string "%a %b %d %H:%M:%S %Y GMT" '(38428 5755 960288 499000))

in the *scratch* buffer echoes "Thu Oct 21 05:59:23 2049 GMT". On the other 
hand, evaluating the exact same function in the *scratch* buffer on the Debian 
system produces the error "Specified time is not representable".  

On Tue, Oct 29, 2019 at 12:51:02AM -0400, Stuart Little wrote:
> Apologies for the uninformative message below. I know slightly more now.
> 
> Setting debug-on-error and running
> 
> M-x eww RET arxiv.org RET
> 
> again produces the following trace:
> 
> --- cut here ---
> 
> Debugger entered--Lisp error: (error "Specified time is not representable")   
>                                                                               
>    
>   format-time-string("%a %b %d %H:%M:%S %Y GMT" (38427 52290 103040 624000) t)
>   url-cookie-handle-set-cookie("browser=68.133.6.220.1572324160979722; 
> path=/; max-age=946080000; domain=.arxiv.org")
>   url-http-handle-cookies()
>   url-http-parse-headers()
>   url-http-chunked-encoding-after-change-function(7029 7034 5)
>   url-http-generic-filter(#<process arxiv.org<1>> "0\015\n\015\n")
>   read-event(nil t 2)
>   sit-for(2)
>   execute-extended-command(nil "eww" "eww")
>   funcall-interactively(execute-extended-command nil "eww" "eww")
>   call-interactively(execute-extended-command nil nil)
>   command-execute(execute-extended-command)
> 
> --- done ---
> 
> This told me the problem was with the url-cookie-handle-set-cookie function; 
> specifically, with the format-time-string directive therein. I tried to 
> fiddle with it to confirm. Indeed, replacing the relevant if-then-else clause
> 
> --- cut ---
> 
> (if (and max-age (string-match "\\`-?[0-9]+\\'" max-age))                     
>                                                                             
>        (setq expires (format-time-string "%a %b %d %H:%M:%S %Y GMT"           
>                                                                               
>   
>                                          (time-add nil (read max-age))        
>                                                                               
>   
>                                          t))                                  
>                                                                               
>   
>       (setq expires (cdr-safe (assoc-string "expires" args t))))
> 
> --- done ---
> 
> therein with just the else branch
> 
> (setq expires (cdr-safe (assoc-string "expires" args t)))
> 
> resolves the issue. arxiv.org loads fine with the redefined 
> url-cookie-handle-set-cookie function. 
> 
> On Mon, Oct 28, 2019 at 08:32:45PM -0400, Stuart Little wrote:
> > I am on a Debian 10.1 machine i686. The current Emacs version in this 
> > Debian repo is 26.1.
> > 
> > My issue is that
> > 
> > M-x eww RET arxiv.org RET
> > 
> > fails to load the page and produces the error
> > 
> > error in process filter: Specified time is not representable
> > 
> > in the minibuffer. Other websites load fine (e.g. nytimes.com, 
> > theguardian.comn, google.com). Others, on the other hand, simply silently 
> > time out: duckduckgo.com and thenation.com behave this way (the minibuffer 
> > reports 'contacting host' but the page never loads).
> > 
> > Everything loads fine on an Arch Linux x86_64 machine running Emacs 26.3 as 
> > well as an Android 9 phone running an ARM version of Emacs 26.3 in a 
> > terminal emulator (Termux), so it is not a network issue.
> > 
> > Additionally, a separate machine running Linux Mint 19.2 an Emacs 25.2.2 
> > loads arxiv.org without issue.