Merge pull request #1810 from billsacks/infnan_unit_test

Allow running infnan unit tests even in DEBUG mode
Up until now, we have been skipping the shr_infnan unit tests when
building in DEBUG mode. Since we pretty much always build the unit tests
in DEBUG mode, that means that we're pretty much never running the
shr_infnan unit tests.

In trying (and failing) to solve #1763, I came up with a way to get the
shr_infnan unit tests to run and pass even when building in debug
mode. That is implemented here.

Test suite: ./scripts_regression_tests.py N_TestUnitTest on cheyenne
Also, cime fortran unit tests on my mac (with gnu)
Test baseline: N/A
Test namelist changes: none
Test status: bit for bit

Fixes #1809

User interface changes?: no

Update gh-pages html (Y/N)?: N

Code review:jedwards

src/share/test/unit/shr_infnan_test/CMakeLists.txt

@@ -8,24 +8,7 @@ add_executable(infnan_test_exe ${test_sources})
 
 declare_generated_dependencies(infnan_test_exe "${share_genf90_sources}")
 
-if("${CMAKE_BUILD_TYPE}" MATCHES CESM_DEBUG)
-  set(FPES_ARE_TRAPPED TRUE)
-endif()
+# Add the actual test.
+add_test(infnan infnan_test_exe)
 
-if(NOT FPES_ARE_TRAPPED)
-
-  # Add the actual test.
-  add_test(infnan infnan_test_exe)
-
-  define_Fortran_stop_failure(infnan)
-
-else()
-
-  # CESM_DEBUG turns on floating point trapping, causing checks in this
-  # test to fail. We'd like the users to be able to see that the test
-  # was skipped but didn't fail, but CTest has no mechanism for this.
-  # Instead, hack around it by adding a test that will always pass but
-  # is likely to stand out as a skipped test.
-  add_test(SKIPPED_infnan true)
-
-endif()
+define_Fortran_stop_failure(infnan)

src/share/test/unit/shr_infnan_test/test_infnan.F90

@@ -10,10 +10,14 @@ program test_infnan
 use shr_kind_mod, only: r4 => shr_kind_r4
 use shr_kind_mod, only: i8 => shr_kind_i8
 use shr_kind_mod, only: i4 => shr_kind_i4
+use, intrinsic :: ieee_exceptions, only : ieee_status_type, ieee_get_status, ieee_set_status
+use, intrinsic :: ieee_exceptions, only : ieee_set_halting_mode
+use, intrinsic :: ieee_exceptions, only : ieee_invalid, ieee_divide_by_zero
 use shr_infnan_mod
 
 implicit none
 
+type(ieee_status_type) :: status_value
 real(r8) :: x, zero
 real(r4) :: y
 real(r8) :: r8array(100), r82Darray(10,10), r83Darray(4,4,4)
@@ -30,6 +34,12 @@ program test_infnan
 integer(i4), parameter :: spnanspat = int(Z'7FC10000',i4)
 intrinsic :: count
 
+! Get initial ieee status so we can restore it later
+call ieee_get_status(status_value)
+
+! Need to turn off ieee_invalid checks for some of these tests to pass
+call ieee_set_halting_mode([ieee_invalid, ieee_divide_by_zero], .false.)
+
 inf = transfer(dpinfpat,inf)
 nan = transfer(dpnanpat,nan)
 nans = transfer(dpnanspat,nans)
@@ -141,6 +151,13 @@ program test_infnan
 y = shr_infnan_to_r4(shr_infnan_neginf)
 call assert(       shr_infnan_isneginf( y ),  "Test that shr_infnan_to_r4(shr_infnan_neginf) sets r4 to -inf" )
 
+! Restore original status
+!
+! At least with gfortran, this restoration prevents floating point exceptions from being
+! raised at the end of the run. Alternatively, we could probably set various flags to
+! .false., using ieee_set_flag.
+call ieee_set_status(status_value)
+
 contains
 
   subroutine assert(val, msg)