Re: Suspicious warning in W64 build

[Paul Eggert]

Eli Zaretskii wrote:
> Not sure what to do about this.  Add 'volatile' to the declaration of
> 'c'?

Looks like a GCC bug. To work around it, please try CACHEABLE instead of 
volatile, to warn the reader that it's a compiler-bug workaround. Like this:

  struct handler *CACHEABLE c = handlerlist->nextfree;


> This seems to imply that m4/manywarnings.m4 has a bug: it somehow
> deduces that a 64-bit Windows build can only allocate up to LONG_MAX
> bytes.

That is due to a limitation in AC_COMPUTE_INT: it can't handle numbers larger 
than LONG_MAX. I attempted to work around this limitation by changing Gnulib to 
assume that the correct value is 2**63 - 1 if it doesn't fit in 'long', and by 
merging the latest Gnulib into the emacs-26 branch. Please give it a try.