p5-math-longdouble @0.22: error: implicitly declaring library function 'finite'

[ryandesign (Ryan Carsten Schmidt)]

​https://build.macports.org/builders/ports-11_arm64-builder/builds/980/steps/install-port/logs/stdio

LongDouble.xs:1747:10: error: implicitly declaring library function 'finite' with type 'int (double)' [-Werror,-Wimplicit-function-declaration]
  return finite(*op);
         ^
LongDouble.xs:1747:10: note: include the header <math.h> or explicitly provide a declaration for 'finite'

[chrstphrchvz (Christopher Chavez)]

I wonder if the module is supposed to be using finitel() instead, i.e. this is a bug rather than a missing header.

[ryandesign (Ryan Carsten Schmidt)]

Is there such a thing as finitel on macOS?

[kencu (Ken)]

see #61547 where isfinite was used.

[chrstphrchvz (Christopher Chavez)]

Never mind, I see that finite() is deprecated on macOS in favor the isfinite() macro which checks the size of the operand.

This module isn't as useful on ARM 64-bit where double and long double are identical.

[chrstphrchvz (Christopher Chavez)]

On 10.15, I only get the deprecation warning for finite(), not an implicit function declaration error. Maybe something is including <math.h> on 10.15, but not 11.

[ryandesign (Ryan Carsten Schmidt)]

Per comment:ticket:61547:3 finite is only defined on i386 and x86_64, hence why the implicit function declaration error was reported here on arm64.