Building 12.3 from source on Mac

Hi,

I'm not sure this is the right list, but I have a problem concerning building PostgreSQL 12.3 from source on a Mac.

I do:

./configure \
    --prefix=${pgTargetDir} \
    --enable-nls \
    --with-perl \
    --with-python \
    --with-libxml \
    --with-tclconfig=/usr/lib64 \
    PG_SYSROOT=$(xcodebuild -version -sdk macosx Path)

and I get:

...
checking for __cpuid... no
checking for _mm_crc32_u8 and _mm_crc32_u32 with CFLAGS=... no
checking for _mm_crc32_u8 and _mm_crc32_u32 with CFLAGS=-msse4.2... yes
checking for __crc32cb, __crc32ch, __crc32cw, and __crc32cd with CFLAGS=... no
checking for __crc32cb, __crc32ch, __crc32cw, and __crc32cd with CFLAGS=-march=armv8-a+crc... no
checking which CRC-32C implementation to use... SSE 4.2 with runtime check
checking which semaphore API to use... System V
checking for /dev/urandom... yes
checking which random number source to use... /dev/urandom
checking for library containing bind_textdomain_codeset... no
configure: error: a gettext implementation is required for NLS

If I leave out --enable-nls then building works fine and I get everything without error. But why is there a problem
withgettext? 

My Mac:

MacBook Pro (Retina, 15-inch, Late 2013)
macOS Catalina 10.15.6 (all updates installed)
Xcode 11.6 (11E708) w/ command line tools installed
No brew, no MacPorts, or other stuff like this is installed.

Does anyone have an idea? Thanks in advance.

Cheers,
Paul