Ninja: Skip Fortran preprocessing if Fortran_PREPROCESS is OFF

If `Fortran_PREPROCESS` is explicitly turned off for a source file then
we know it does not need to be preprocessed.  Teach the Ninja generator
to skip preprocessing in this case.  Otherwise we still must preprocess
just in case.

Fixes: #18870

1 files changed, 22 insertions, 24 deletions

diff --git a/Tests/FortranOnly/CMakeLists.txt b/Tests/FortranOnly/CMakeLists.txt
index 59f139b..d24df2d 100644
--- a/Tests/FortranOnly/CMakeLists.txt
+++ b/Tests/FortranOnly/CMakeLists.txt
@@ -135,29 +135,27 @@ if(test_pp_flags)
   set_property(SOURCE preprocess3.f PROPERTY Fortran_PREPROCESS ON)
 endif()
 
-if(NOT CMAKE_GENERATOR MATCHES "Ninja")
-  # Test that neither the compiler nor CMake performs unnecessary preprocessing.
-  add_library(no_preprocess_target_lower STATIC no_preprocess_target_lower.f)
-  target_compile_options(no_preprocess_target_lower PRIVATE -DINTEGER=nonsense)
-  set_property(TARGET no_preprocess_target_lower PROPERTY Fortran_PREPROCESS OFF)
-  add_library(no_preprocess_source_lower STATIC no_preprocess_source_lower.f)
-  target_compile_options(no_preprocess_source_lower PRIVATE -DINTEGER=nonsense)
-  set_property(SOURCE no_preprocess_source_lower.f PROPERTY Fortran_PREPROCESS OFF)
-
-  # Test that we can explicitly not preprocess a target or source.
-  # This will not work on certain compilers due to either missing a
-  # "don't preprocess" flag, or due to choice of file extension.
-  if(test_pp_flags AND NOT CMAKE_Fortran_COMPILER_ID MATCHES "(Flang|NAG|PGI|SunPro|XL)")
-    add_library(no_preprocess_target STATIC no_preprocess_target_upper.F)
-    target_compile_options(no_preprocess_target PRIVATE -DINTEGER=nonsense)
-    add_library(no_preprocess_source STATIC no_preprocess_source_upper.F)
-    target_compile_options(no_preprocess_source PRIVATE -DINTEGER=nonsense)
-    if(NOT CMAKE_Fortran_COMPILER_ID STREQUAL "Cray"
-        AND NOT "${CMAKE_Fortran_COMPILER_ID};${CMAKE_Fortran_SIMULATE_ID}" STREQUAL "Intel;MSVC")
-      target_sources(no_preprocess_target PRIVATE no_preprocess_target_fpp.fpp)
-      target_sources(no_preprocess_source PRIVATE no_preprocess_source_fpp.fpp)
-    endif()
-    set_property(TARGET no_preprocess_target PROPERTY Fortran_PREPROCESS OFF)
-    set_property(SOURCE no_preprocess_source_upper.F no_preprocess_source_fpp.fpp PROPERTY Fortran_PREPROCESS OFF)
+# Test that neither the compiler nor CMake performs unnecessary preprocessing.
+add_library(no_preprocess_target_lower STATIC no_preprocess_target_lower.f)
+target_compile_options(no_preprocess_target_lower PRIVATE -DINTEGER=nonsense)
+set_property(TARGET no_preprocess_target_lower PROPERTY Fortran_PREPROCESS OFF)
+add_library(no_preprocess_source_lower STATIC no_preprocess_source_lower.f)
+target_compile_options(no_preprocess_source_lower PRIVATE -DINTEGER=nonsense)
+set_property(SOURCE no_preprocess_source_lower.f PROPERTY Fortran_PREPROCESS OFF)
+
+# Test that we can explicitly not preprocess a target or source.
+# This will not work on certain compilers due to either missing a
+# "don't preprocess" flag, or due to choice of file extension.
+if(test_pp_flags AND NOT CMAKE_Fortran_COMPILER_ID MATCHES "(Flang|NAG|PGI|SunPro|XL)")
+  add_library(no_preprocess_target STATIC no_preprocess_target_upper.F)
+  target_compile_options(no_preprocess_target PRIVATE -DINTEGER=nonsense)
+  add_library(no_preprocess_source STATIC no_preprocess_source_upper.F)
+  target_compile_options(no_preprocess_source PRIVATE -DINTEGER=nonsense)
+  if(NOT CMAKE_Fortran_COMPILER_ID STREQUAL "Cray"
+      AND NOT "${CMAKE_Fortran_COMPILER_ID};${CMAKE_Fortran_SIMULATE_ID}" STREQUAL "Intel;MSVC")
+    target_sources(no_preprocess_target PRIVATE no_preprocess_target_fpp.fpp)
+    target_sources(no_preprocess_source PRIVATE no_preprocess_source_fpp.fpp)
   endif()
+  set_property(TARGET no_preprocess_target PROPERTY Fortran_PREPROCESS OFF)
+  set_property(SOURCE no_preprocess_source_upper.F no_preprocess_source_fpp.fpp PROPERTY Fortran_PREPROCESS OFF)
 endif()