unable to determine default plugin path

[tbonfort]

From what I have researched, it is currently not possible to reliably determine the default gdalplugins lib path for out-of-source drivers/plugins (due to "lib" vs "lib64" directory names).

Could gdal-config be extended with a --plugindir option to print it out ? (as there doesn't seem to be a standard option to print this out with pkg-config)

Furthermore, there seems to be some inconsistencies in the generated gdal.pc file (note the invalid but unused value for $libdir)

CONFIG_VERSION=3.8.0
CONFIG_INST_PREFIX=/opt
CONFIG_INST_LIBS=-L/opt/lib64 -lgdal
CONFIG_INST_CFLAGS=-I/opt/include
CONFIG_INST_DATA=/opt/share/gdal
prefix=${CONFIG_INST_PREFIX}
exec_prefix=${prefix}
libdir=${exec_prefix}/lib
includedir=${exec_prefix}/include
datadir=${CONFIG_INST_DATA}

Name: libgdal
Description: Geospatial Data Abstraction Library
Version: ${CONFIG_VERSION}
Libs: ${CONFIG_INST_LIBS}
Libs.private: -ldl -lssl -lcrypto -lzstd -ljxl -lgeos_c -lcurl -lproj -lstdc++ -lm
Cflags: ${CONFIG_INST_CFLAGS}