Detect fftwf only if ENABLE_FLOAT_FFTW

Author: Growl1234

.github/workflows/cuda.yml

@@ -46,7 +46,7 @@ jobs:
           nvidia-smi
           source toolchain/install/setup
           rm -rf build
-          cmake -B build -G Ninja -DUSE_CUDA=ON -DBUILD_TESTING=ON
+          cmake -B build -G Ninja -DUSE_CUDA=ON -DBUILD_TESTING=ON -DENABLE_FLOAT_FFTW=ON
           cmake --build build -j4
           cmake --install build
 

cmake/FindFFTW3.cmake

@@ -16,29 +16,35 @@ find_library(FFTW3_LIBRARY
     HINTS ${FFTW3_DIR}
     PATH_SUFFIXES "lib"
     )
-find_library(FFTW3_FLOAT_LIBRARY
-    NAMES fftw3f
-    HINTS ${FFTW3_DIR}
-    PATH_SUFFIXES "lib"
-    )
 
-# both libfftw3.so and libfftw3_omp.so should be link in multi-thread term
+if(ENABLE_FLOAT_FFTW)
+  find_library(FFTW3_FLOAT_LIBRARY
+      NAMES fftw3f
+      HINTS ${FFTW3_DIR}
+      PATH_SUFFIXES "lib"
+      )
+endif()
+
+# Both libfftw3.so and libfftw3_omp.so are required for OpenMP builds.
 if (USE_OPENMP)
-find_library(FFTW3_OMP_LIBRARY
-    NAMES fftw3_omp
-    HINTS ${FFTW3_DIR}
-    PATH_SUFFIXES "lib"
-    )
+  find_library(FFTW3_OMP_LIBRARY
+      NAMES fftw3_omp
+      HINTS ${FFTW3_DIR}
+      PATH_SUFFIXES "lib"
+      )
 endif()
 
 # Handle the QUIET and REQUIRED arguments and
 # set FFTW3_FOUND to TRUE if all variables are non-zero.
 include(FindPackageHandleStandardArgs)
-if (USE_OPENMP)
-find_package_handle_standard_args(FFTW3 DEFAULT_MSG FFTW3_OMP_LIBRARY FFTW3_LIBRARY FFTW3_FLOAT_LIBRARY FFTW3_INCLUDE_DIR)
-else()
-find_package_handle_standard_args(FFTW3 DEFAULT_MSG FFTW3_LIBRARY FFTW3_FLOAT_LIBRARY FFTW3_INCLUDE_DIR)
+set(_fftw3_required_vars FFTW3_LIBRARY FFTW3_INCLUDE_DIR)
+if(USE_OPENMP)
+  list(APPEND _fftw3_required_vars FFTW3_OMP_LIBRARY)
+endif()
+if(ENABLE_FLOAT_FFTW)
+  list(APPEND _fftw3_required_vars FFTW3_FLOAT_LIBRARY)
 endif()
+find_package_handle_standard_args(FFTW3 DEFAULT_MSG ${_fftw3_required_vars})
 
 # Copy the results to the output variables and target.
 if(FFTW3_FOUND)
@@ -64,7 +70,7 @@ if(FFTW3_FOUND)
             IMPORTED_LOCATION "${FFTW3_LIBRARY}"
             INTERFACE_INCLUDE_DIRECTORIES "${FFTW3_INCLUDE_DIRS}")
     endif()
-    if(NOT TARGET FFTW3::FFTW3_FLOAT)
+    if(ENABLE_FLOAT_FFTW AND NOT TARGET FFTW3::FFTW3_FLOAT)
         add_library(FFTW3::FFTW3_FLOAT UNKNOWN IMPORTED)
         set_target_properties(FFTW3::FFTW3_FLOAT PROPERTIES
                 IMPORTED_LINK_INTERFACE_LANGUAGES "C"