Re: MacOS 64-bit build

[Hans Åberg]

> On 9 Jan 2020, at 18:00, Werner LEMBERG <address@hidden> wrote:
> 
>>> There is no guarantee that `FlexLexer.h` found during compilation
>>> is the one that is used by a recent flex version.  Unfortunately,
>>> `FlexLexer.h` doesn't contain any version information, so it is
>>> really impossible to protect against this situation automatically.
>> 
>> Akim Demaille made a patch for it, see:
>> https://lists.gnu.org/archive/html/bug-bison/2018-09/msg00020.html
> 
> Nope, he didn't.  This patch is for something completely different, as
> far as I can see – LilyPond doesn't use `FlexLexer.hh`, it rather uses
> `FlexLexer.h` that comes with flex.

I did not look so careful at it, but I get the impression he makes his own 
header that depends on the Flex version.

> If you look into the git repository of flex you can see that even the
> most recent version of `FlexLexer.h` doesn't have any version
> information.

You can’t get around that, so one way around it is to make ones own header and 
include that. Then the .cc uses system includes, so either that should be 
patched too, or an option passed to the compiler.