Disable long double builds in MSVC with preprocessor

Author: egpbos

.appveyor.yml

@@ -45,9 +45,6 @@ environment:
       FFTW_INSTALL_MODE: official
       FFTW_ROOT: C:\fftw_download
 
-      # TODO: conda-forge build doen, CMakeLists aanpassen zodat FFTW_LONGDOUBLE niet required is bij CMAKE_CXX_COMPILER_ID == MSVC
-      # sowieso is libs requiren beetje raar als je alleen installeert;
-      # mss beter om als ze niet gevonden zijn de test/bench builds uit te zetten
       # TODO: goed idee (?): een MSVC_FFTW_LONGDOUBLE_LINKING_WORKAROUND option toevoegen die manually een long double lib downloadt zodat de tests iig linken, maar met een melding dat die dus niet goed draaien
 
 matrix:
@@ -117,9 +114,7 @@ install:
   - nmake test_xtensor-fftw
 
 before_build:
-#  - copy C:\fftw_download\*.* test
   - cd test
 
 build_script:
-  # The long double FFTW library only works when sizeof(long double) == 12. In recent VC versions, long double is an alias of double, and so long double will not work with fftw3l. The long double tests are usually third in the list, so index 2 starting from 0, e.g. "TransformAndInvert/2".
-  - test_xtensor-fftw.exe --gtest_filter=-*/2*
+  - test_xtensor-fftw.exe

CMakeLists.txt

@@ -58,21 +58,35 @@ endif()
 set(CMAKE_CXX_STANDARD 14)
 set(CMAKE_CXX_STANDARD_REQUIRED YES)
 set(CMAKE_CXX_EXTENSIONS NO)
+
 # includes
+
 # .. our own
 include_directories(${XTENSOR_FFTW_INCLUDE_DIR})
+
 # .. xtensor
 find_package(xtensor REQUIRED)
 message(STATUS "Found xtensor: ${xtensor_INCLUDE_DIRS}/xtensor")
 include_directories(${xtensor_INCLUDE_DIRS})
+
 # .. xtl
 find_package(xtl REQUIRED)
 message(STATUS "Found xtl: ${xtl_INCLUDE_DIRS}/xtl")
 include_directories(${xtl_INCLUDE_DIRS})
+
 # .. fftw
-find_package(FFTW REQUIRED
-        COMPONENTS FLOAT_LIB DOUBLE_LIB LONGDOUBLE_LIB)
+if(MSVC)
+    # no long double component, since in the Windows conda-forge build it is not available
+    # and the "official" prebuilt long double library can only be used from MinGW
+    find_package(FFTW REQUIRED
+            COMPONENTS FLOAT_LIB DOUBLE_LIB)
+    add_definitions(-DFFTW_NO_LONGDOUBLE)
+else()
+    find_package(FFTW REQUIRED
+            COMPONENTS FLOAT_LIB DOUBLE_LIB LONGDOUBLE_LIB)
+endif(MSVC)
 include_directories(${FFTW_INCLUDE_DIRS})
+
 # warnings (gcc and clang)
 if (COMPILE_WARNINGS)
     add_compile_options(-Wundef -Wshadow -Wwrite-strings -Wredundant-decls -Woverloaded-virtual -Wcast-qual -Wcast-align -Wpointer-arith -Wconversion -Wold-style-cast -Wall -Wextra)

bench/basic_interface.cpp

@@ -129,6 +129,7 @@ BENCHMARK_F(rfft2Dxarray_float, TransformAndInvert_nD)(::benchmark::State& st) {
 //  }
 //}
 //
+//#ifndef FFTW_NO_LONGDOUBLE
 //BENCHMARK_TEMPLATE_F(rfft1Dxarray, TransformAndInvert, long double)(::benchmark::State& st) {
 //  for (auto _ : st) {
 //    auto a_fourier = xt::fftw::rfft(a);
@@ -137,6 +138,7 @@ BENCHMARK_F(rfft2Dxarray_float, TransformAndInvert_nD)(::benchmark::State& st) {
 //    ::benchmark::DoNotOptimize(should_be_a);
 //  }
 //}
+//#endif  // FFTW_NO_LONGDOUBLE
 
 
 BENCHMARK_MAIN()

test/CMakeLists.txt

@@ -104,7 +104,7 @@ add_executable(${XTENSOR_FFTW_TARGET} ${XTENSOR_FFTW_TESTS} ${XTENSOR_HEADERS} $
 if(DOWNLOAD_GTEST OR GTEST_SRC_DIR)
     add_dependencies(${XTENSOR_FFTW_TARGET} gtest_main)
 endif()
-target_link_libraries(${XTENSOR_FFTW_TARGET} ${GTEST_BOTH_LIBRARIES} ${CMAKE_THREAD_LIBS_INIT}  ${FFTW_FLOAT_LIB} ${FFTW_DOUBLE_LIB} ${FFTW_LONGDOUBLE_LIB})
+target_link_libraries(${XTENSOR_FFTW_TARGET} ${GTEST_BOTH_LIBRARIES} ${CMAKE_THREAD_LIBS_INIT}  ${FFTW_LIBRARIES})
 
 add_custom_target(xtest COMMAND test_xtensor-fftw DEPENDS ${XTENSOR_FFTW_TARGET})
 

test/basic_interface.cpp

@@ -30,7 +30,11 @@ template <typename T>
 class TransformAndInvert : public ::testing::Test {};
 
 // the GoogleTest list of typed test cases
+#ifdef FFTW_NO_LONGDOUBLE
+typedef ::testing::Types<float, double> MyTypes;
+#else
 typedef ::testing::Types<float, double, long double> MyTypes;
+#endif  // FFTW_NO_LONGDOUBLE
 TYPED_TEST_CASE(TransformAndInvert, MyTypes);
 
 // Generates a dim-dimensional array of size n in each dimension, filled with random numbers between 0 and the numeric