gcc 14+ and m68k build failure

gcc 14+ and m68k build failure

[Joel Sherrill]

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Hi

GCC 14+ fail to build a few newlib targets. I am looking into m68k-rtems
(m68k-elf) first. If there is a common thread, it appears to be related to
targets which do not have long double in all multilibs.

First, how do you see more than "CC..file.c"?

The error for m68k starts with this:

ake[3]: Entering directory
'/home/joel/test-gcc/b-m68k-rtems6-gcc/m68k-rtems6/newlib'
  CC       libm/complex/libm_a-ccoshl.o
../../../gcc/newlib/libm/complex/ccoshl.c: In function 'ccoshl':
../../../gcc/newlib/libm/complex/ccoshl.c:43:13: error: implicit
declaration of function 'coshl'; did you mean 'coshf'?
[-Wimplicit-function-declaration]
   43 |         w = coshl(x) * cosl(y) + (sinhl(x) * sinl(y)) * I;
      |             ^~~~~
      |             coshf
../../../gcc/newlib/libm/complex/ccoshl.c:43:24: error: implicit
declaration of function 'cosl'; did you mean 'cosf'?
[-Wimplicit-function-declaration]
   43 |         w = coshl(x) * cosl(y) + (sinhl(x) * sinl(y)) * I;


I suspect that since only one multilib for m68k has multilib and that is
picked at compile time, the multilib here isn't enabling the prototypes for
long double. That idea seems right but the code doesn't seem to always
follow up to avoid trying to compile files like the above which assume long
double.

Ideas appreciated.

--joel

Re: gcc 14+ and m68k build failure

[Hans-Bernhard Bröker]

Am 02.06.2024 um 17:58 schrieb Joel Sherrill:

> First, how do you see more than "CC..file.c"?

Run configure with "--disable-silent-rules", or run make with an 
argument of "V=1".

If you're sure you never want this, you can add "enable_silent_rules=no" 
to your local or personal "config.site" file.

For the gory details, please see

	info automake silencing Automake

Re: gcc 14+ and m68k build failure

[Pietro Monteiro]

On Sun, Jun 2, 2024, at 8:58 AM, Joel Sherrill wrote:
> Hi
>
> GCC 14+ fail to build a few newlib targets. I am looking into m68k-rtems
> (m68k-elf) first. If there is a common thread, it appears to be related to
> targets which do not have long double in all multilibs.

The same thing is happening on SH for the m4-single-only multilib.

> First, how do you see more than "CC..file.c"?

Add `V=1' to you make invocation.
 
> The error for m68k starts with this:
>
> ake[3]: Entering directory
> '/home/joel/test-gcc/b-m68k-rtems6-gcc/m68k-rtems6/newlib'
>   CC       libm/complex/libm_a-ccoshl.o
> ../../../gcc/newlib/libm/complex/ccoshl.c: In function 'ccoshl':
> ../../../gcc/newlib/libm/complex/ccoshl.c:43:13: error: implicit
> declaration of function 'coshl'; did you mean 'coshf'?
> [-Wimplicit-function-declaration]
>    43 |         w = coshl(x) * cosl(y) + (sinhl(x) * sinl(y)) * I;
>       |             ^~~~~
>       |             coshf
> ../../../gcc/newlib/libm/complex/ccoshl.c:43:24: error: implicit
> declaration of function 'cosl'; did you mean 'cosf'?
> [-Wimplicit-function-declaration]
>    43 |         w = coshl(x) * cosl(y) + (sinhl(x) * sinl(y)) * I;
>
>
> I suspect that since only one multilib for m68k has multilib and that is
> picked at compile time, the multilib here isn't enabling the prototypes for
> long double. That idea seems right but the code doesn't seem to always
> follow up to avoid trying to compile files like the above which assume long
> double.

I think I understand what's going on. `_LDBL_EQ_DBL' is not being defined for that multilib. So, functions like `coshl' aren't compiled (see newlib/libm/common/coshl.c), but the complex versions of the functions don't have the `#ifdef _LDBL_EQ_DBL' guard around them (see: newlib/libm/complex/ccoshl.c). And GCC 14 changed the lack of a function declaration from a warning into an error.

> Ideas appreciated.

I'll try to post a patch adding the ifdefs to add long double complex functions. 

> --joel

pietro

Re: gcc 14+ and m68k build failure

[Pietro Monteiro]

On Mon, Jun 3, 2024, at 9:02 PM, Pietro Monteiro wrote:

> I'll try to post a patch adding the ifdefs to add long double complex 
> functions. 

Can you try my the patch i just sent[0]?

[0] https://inbox.sourceware.org/newlib/0ca79433-448c-469f-880a-6b228ade4b80@app.fastmail.com/

pietro.