Avoid runtime checks (#16)

Author: awvwgk

config/CMakeLists.txt

@@ -32,14 +32,14 @@ if(NOT CMAKE_BUILD_TYPE AND NOT CMAKE_CONFIGURATION_TYPES)
   )
 endif()
 
-include(CheckFortranSourceRuns)
-check_fortran_source_runs(
-  "if (selected_real_kind(33) == -1) stop 1; end"
+include(CheckFortranSourceCompiles)
+check_fortran_source_compiles(
+  "integer, parameter :: qp = selected_real_kind(33); complex(qp) :: x; end"
   WITH_QP
 )
 set(WITH_QP ${WITH_QP} PARENT_SCOPE)
-check_fortran_source_runs(
-  "if (any(selected_real_kind(18) == [-1, selected_real_kind(33)])) stop 1; end"
+check_fortran_source_compiles(
+  "integer, parameter :: xdp = merge(-1, selected_real_kind(18), selected_real_kind(18) == selected_real_kind(33)); complex(xdp) :: x; end"
   WITH_XDP
 )
 set(WITH_XDP ${WITH_XDP} PARENT_SCOPE)

config/meson.build

@@ -54,8 +54,8 @@ if get_option('openmp')
   lib_deps += omp_dep
 endif
 
-with_qp = fc.run('if (selected_real_kind(33) == -1) stop 1; end').returncode() == 0
-with_xdp = fc.run('if (any(selected_real_kind(18) == [-1, selected_real_kind(33)])) stop 1; end').returncode() == 0
+with_qp = fc.compiles('integer, parameter :: qp = selected_real_kind(33); complex(qp) :: x; end')
+with_xdp = fc.compiles('integer, parameter :: xdp = merge(-1, selected_real_kind(18),selected_real_kind(18) == selected_real_kind(33)); complex(xdp) :: x; end')
 add_project_arguments(
   '-DWITH_QP=@0@'.format(with_qp.to_int()),
   '-DWITH_XDP=@0@'.format(with_xdp.to_int()),