ucx 1.18.0 not building with NVHPC 24.9 with undefined reference

[louspe-linaro]

Describe the bug

Undefined reference when building with NVHPC 24.9

   CC       ucx_info-build_info.o
   CC       ucx_info-proto_info.o
   CC       ucx_info-sys_info.o
   CC       ucx_info-tl_info.o
   CC       ucx_info-type_info.o
   CC       ucx_info-version_info.o
   CC       ucx_info-ucx_info.o
   CCLD     ucx_info
/usr/bin/ld: build/ucx/src/ucs/.libs/libucs.so: undefined reference to `__builtin_ia32_lzcnt_u32'
make[3]: *** [Makefile:591: ucx_info] Error 2

_lzcnt_u32(len) is used in src/ucs/arch/x86_64/cpu.c under flag __LZCNT__ but that is not defined for the NVIDIA compiler.
https://docs.nvidia.com/hpc-sdk/compilers/hpc-compilers-ref-guide/index.html#x86-64-abm-intrinsics

Steps to Reproduce

configure --disable-dependency-tracking --prefix=$HOME/ucx-install --bindir=${prefix}/bin --sbindir=${prefix}/bin --libexecdir=${prefix}/bin --libdir=${prefix}/lib --includedir=${prefix}/include --oldincludedir=${prefix}/include --datarootdir=${prefix}/share

Trying to build v1.18.0

Setup and versions

Observed only on x86_64 with Ubuntu 24.04, SLES 15, RHEL-8, RHEL-9

[tvegas1]

Still checking but seems it could be compiler related since defines itself the use:

 80 static __inline__ unsigned int __DEFAULT_FN_ATTRS
 81 _lzcnt_u32(unsigned int __X)
 82 {
 83   return __builtin_ia32_lzcnt_u32(__X);
 84 }

Repro:

$ cat abc.c
#include <stdio.h>
#include <x86intrin.h>
int main(void)
{
    unsigned int a = 32;
    printf("%u\n", _lzcnt_u32(a));
    return 0;
}
$ nvc abc.c
/tmp/nvcH7nneJO8FPcwQ.o: In function `_lzcnt_u32':
/opt/nvidia/hpc_sdk/Linux_x86_64/24.9/compilers/include/lzcntintrin.h:83: undefined reference to `__builtin_ia32_lzcnt_u32'

[tvegas1]

Also related #10519