Compiling software on top of hwloc's C API

A program using the hwloc C API (for instance with hwloc-hello.c presented in API Example) may be built with standard development tools. pkg-config provides easy ways to retrieve the required compiler and linker flags as described below, but it is not mandatory.

Compiling on top of hwloc's C API with GNU Make

Here's an example of Makefile for building hwloc-hello.c with GNU Make:

CFLAGS += $(shell pkg-config --cflags hwloc)
LDLIBS += $(shell pkg-config --libs hwloc)

hwloc-hello: hwloc-hello.c
        $(CC) hwloc-hello.c $(CFLAGS) -o hwloc-hello $(LDLIBS)

Compiling on top of hwloc's C API with CMake

Here's an example de CMakeLists.txt which shows variables obtained from pkg-config and how to use them:

cmake_minimum_required(VERSION 3.5)
project(TEST_HWLOC C)
include(FindPkgConfig)
if(PKG_CONFIG_EXECUTABLE)
  unset(HWLOC_FOUND CACHE)
  pkg_search_module(HWLOC hwloc)
  if(HWLOC_FOUND)
    message(STATUS "HWLOC_LIBRARIES=${HWLOC_LIBRARIES}")
    message(STATUS "HWLOC_LINK_LIBRARIES=${HWLOC_LINK_LIBRARIES}")
    message(STATUS "HWLOC_LIBRARY_DIRS=${HWLOC_LIBRARY_DIRS}")
    message(STATUS "HWLOC_LDFLAGS=${HWLOC_LDFLAGS}")
    message(STATUS "HWLOC_LDFLAGS_OTHERS=${HWLOC_LDFLAGS_OTHERS}")
    message(STATUS "HWLOC_INCLUDE_DIRS=${HWLOC_INCLUDE_DIRS}")
    message(STATUS "HWLOC_CFLAGS=${HWLOC_CFLAGS}")
    message(STATUS "HWLOC_CFLAGS_OTHER=${HWLOC_CFLAGS_OTHER}")
  else()
    message(FATAL_ERROR "HWLOC not found with pkg-config, add the path to hwloc.pc in PKG_CONFIG_PATH.")
  endif()
else()
  message(FATAL_ERROR "PKG_CONFIG_EXECUTABLE: not found.")
endif()

add_executable(hwloc-hello hwloc-hello.c)
target_include_directories(hwloc-hello PRIVATE ${HWLOC_INCLUDE_DIRS})
target_compile_options(hwloc-hello PRIVATE ${HWLOC_CFLAGS})
target_link_libraries(hwloc-hello PRIVATE ${HWLOC_LINK_LIBRARIES})
target_link_options(hwloc-hello PRIVATE ${HWLOC_LDFLAGS})

The project may be built with:

cmake -B build
cmake --build build --verbose

The built binary is then available under build/hwloc-hello.