From mboxrd@z Thu Jan  1 00:00:00 1970
From: Baruch Siach <baruch@tkos.co.il>
Date: Thu, 11 Oct 2018 14:45:16 +0300
Subject: [Buildroot] Analysis results for 2018-10-09
In-Reply-To: <875zy8spe0.fsf@dell.be.48ers.dk>
References: <20181010060010.4E3C920736@mail.bootlin.com>
 <20181010174814.5ac114f1@windsurf> <87y3b5ks97.fsf@tkos.co.il>
 <87a7nksr18.fsf@dell.be.48ers.dk> <87o9c0lozx.fsf@tkos.co.il>
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To: buildroot@busybox.net

Hi Peter,

Peter Korsgaard writes:
>>>>>> "Baruch" == Baruch Siach <baruch@tkos.co.il> writes:
>  >> -typedef double hbase_f(double);
>  >> +typedef double (*hbase_f)(double);
>
>  > Wouldn't that make the definition 'hbase_f *val_in' a pointer to
>  > function pointer?
>
> Not in C at least. The syntax is:
>
> typedef <returntype> (*name)(<arguments>)
>
> https://stackoverflow.com/questions/1591361/understanding-typedefs-for-function-pointers-in-c

Correct. But consider the SO example code:

  typedef void (*SignalHandler)(int signum);

  extern SignalHandler signal(int signum, SignalHandler handler);

The 'handler' parameter of the signal() function is a pointer to a
function. However the definition

  SignalHandler *handler;

would create a pointer to a pointer. As I understand, this is not the
intention of the 'hbase_f *val_in' definition in the original code.

baruch

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