cmake: remove unused macros from config.h template

[chrisdebian]

Summary

Six macros defined in config.h.cmake are never referenced in any C or header file in the library:

• CPU_IS_LITTLE_ENDIAN
• HAVE_LRINT
• HAVE_LRINTF
• HAVE_STDINT_H
• SIZEOF_INT
• SIZEOF_LONG

These appear to be remnants from when libsamplerate provided its own lrint/lrintf fallbacks and portability shims for older compilers. That code was removed, but the corresponding config.h entries were not.

The if(CPU_IS_BIG_ENDIAN)/set(CPU_IS_LITTLE_ENDIAN) block in CMakeLists.txt is also removed, as it existed solely to populate the now-removed CPU_IS_LITTLE_ENDIAN entry.

Verification

Grepped all .c and .h files under src/ and include/ — none of the six symbols appear anywhere.

$ grep -r "CPU_IS_LITTLE_ENDIAN\|HAVE_LRINT\|HAVE_LRINTF\|HAVE_STDINT_H\|SIZEOF_INT\|SIZEOF_LONG" src/ include/
(no output)

Spotted while using libsamplerate as a vendored CMake submodule in an Android project; the Android Studio C/C++ unused-macro inspection flagged these in the generated config.h.

[chrisdebian]

Hi, a gentle bump on this one after a few months. It's a small, self-contained change (removing unused macros from the config.h.cmake template), so happy to adjust if you'd like anything different, or let me know if it's not a priority.

[erikd]

Sorry, just checked the first one (CPU_IS_LITTLE_ENDIAN) and found many of uses.

> grep CPU_IS_LITTLE_ENDIAN src/*.c
src/aiff.c:	if (CPU_IS_LITTLE_ENDIAN && endian == SF_ENDIAN_CPU)
src/au.c:		if (CPU_IS_LITTLE_ENDIAN && psf->endian == SF_ENDIAN_CPU)
src/caf.c:	else if (CPU_IS_LITTLE_ENDIAN && (psf->endian == SF_ENDIAN_LITTLE || psf->endian == SF_ENDIAN_CPU))
src/common.c:					if (CPU_IS_LITTLE_ENDIAN)
src/common.c:#elif (CPU_IS_LITTLE_ENDIAN == 1)
src/common.c:#elif (CPU_IS_LITTLE_ENDIAN == 1)
src/double64.c:#if CPU_IS_LITTLE_ENDIAN
src/double64.c:	return (CPU_IS_LITTLE_ENDIAN) ? DOUBLE_BROKEN_LE : DOUBLE_BROKEN_BE ;
src/dwd.c:		if (CPU_IS_LITTLE_ENDIAN && psf->endian == SF_ENDIAN_CPU)
src/float32.c:#if CPU_IS_LITTLE_ENDIAN
src/float32.c:	return (CPU_IS_LITTLE_ENDIAN) ? FLOAT_BROKEN_LE : FLOAT_BROKEN_BE ;
src/mat4.c:		if (CPU_IS_LITTLE_ENDIAN && (psf->endian == SF_ENDIAN_CPU || psf->endian == 0))
src/mat5.c:		if (CPU_IS_LITTLE_ENDIAN && (psf->endian == SF_ENDIAN_CPU || psf->endian == 0))
src/mat5.c:		if (CPU_IS_LITTLE_ENDIAN) version = ENDSWAP_16 (version) ;
src/mat5.c:	if ((CPU_IS_LITTLE_ENDIAN && endian == IM_MARKER) ||
src/paf.c:		if (endian == SF_ENDIAN_LITTLE || (CPU_IS_LITTLE_ENDIAN && (endian == SF_ENDIAN_CPU)))
src/paf.c:	if ((CPU_IS_BIG_ENDIAN && psf->endian == SF_ENDIAN_LITTLE) || (CPU_IS_LITTLE_ENDIAN && psf->endian == SF_ENDIAN_BIG))
src/paf.c:	if (CPU_IS_LITTLE_ENDIAN)
src/pcm.c:#if CPU_IS_LITTLE_ENDIAN
src/pcm.c:#if CPU_IS_LITTLE_ENDIAN
src/pcm.c:#if CPU_IS_LITTLE_ENDIAN
src/pcm.c:#if CPU_IS_LITTLE_ENDIAN
src/raw.c:	else if (CPU_IS_LITTLE_ENDIAN && (psf->endian == 0 || psf->endian == SF_ENDIAN_CPU))
src/sd2.c:	if (CPU_IS_LITTLE_ENDIAN)
src/sndfile.c:		#if (CPU_IS_LITTLE_ENDIAN == 1)
src/svx.c:		if (psf->endian == SF_ENDIAN_LITTLE || (CPU_IS_LITTLE_ENDIAN && psf->endian == SF_ENDIAN_CPU))

[erikd]

Does not seem correct.

[chrisdebian]

You're right, sorry — I checked CPU_IS_LITTLE_ENDIAN more carefully and it's genuinely used across src/*.c (aiff.c, au.c, caf.c, common.c, double64.c, dwd.c, float32.c, mat4.c, mat5.c, paf.c, pcm.c, raw.c, sd2.c, sndfile.c, svx.c). Pushed a fix restoring its definition in both CMakeLists.txt and config.h.cmake. I also double-checked the other five macros this PR removes (HAVE_LRINT, HAVE_LRINTF, HAVE_STDINT_H, SIZEOF_INT, SIZEOF_LONG) and confirmed none of them have any remaining references anywhere else in the repo, so those stay removed.

[erikd]

I am also a little concerned that before you restored CPU_IS_LITTLE_ENDIAN CI passed with flying colors.

Any idea why this was not caught by any of the cmake CI builds?

[chrisdebian]

Hi Erik, thanks for checking, and sorry for the confusion.

I think this is a mix-up between the two repos. I just grepped libsndfile's own source tree, and all 15 of those files (aiff.c, au.c, caf.c, etc.) do use CPU_IS_LITTLE_ENDIAN there. But this PR is against libsamplerate, and I can't find CPU_IS_LITTLE_ENDIAN (or any of the other five removed macros) anywhere in libsamplerate's own src/ or include/ files. That also answers your CI question: the macro genuinely isn't referenced in this codebase, so nothing broke when it was removed.

I've reverted my earlier restore commit so the PR is back to the original clean removal. Let me know if you'd like me to double-check anything else.