diff --git a/CMakeLists.txt b/CMakeLists.txt
index b461f7d40..52ab21e64 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -144,18 +144,18 @@ set (STANDARD_CHECK_gfortran "-std=f2008ts -pedantic-errors" )
 #     all:
 #  -name as_is: case sensitive Fortran!
 ###################################################################################################
-set (COMPILE_OPTIONS_ifort   "${COMPILE_OPTIONS_ifort} -DDAMASKVERSION=\"${DAMASK_V}\""  )
-set (COMPILE_OPTIONS_ifort   "${COMPILE_OPTIONS_ifort} -fpp"                             )
-set (COMPILE_OPTIONS_ifort   "${COMPILE_OPTIONS_ifort} -ftz"                             )
-set (COMPILE_OPTIONS_ifort   "${COMPILE_OPTIONS_ifort} -assume byterecl,fpe_summary"     )
-set (COMPILE_OPTIONS_ifort   "${COMPILE_OPTIONS_ifort} -diag-disable 5268"               )
-set (COMPILE_OPTIONS_ifort   "${COMPILE_OPTIONS_ifort} -warn declarations"               )
-set (COMPILE_OPTIONS_ifort   "${COMPILE_OPTIONS_ifort} -warn general"                    )
-set (COMPILE_OPTIONS_ifort   "${COMPILE_OPTIONS_ifort} -warn usage"                      )
-set (COMPILE_OPTIONS_ifort   "${COMPILE_OPTIONS_ifort} -warn interfaces"                 )
-set (COMPILE_OPTIONS_ifort   "${COMPILE_OPTIONS_ifort} -warn ignore_loc"                 )
-set (COMPILE_OPTIONS_ifort   "${COMPILE_OPTIONS_ifort} -warn alignments"                 )
-set (COMPILE_OPTIONS_ifort   "${COMPILE_OPTIONS_ifort} -warn unused"                     )
+set (COMPILE_OPTIONS_ifort   "${COMPILE_OPTIONS_ifort} -DDAMASKVERSION=${DAMASK_V}" )
+set (COMPILE_OPTIONS_ifort   "${COMPILE_OPTIONS_ifort} -fpp"                        )
+set (COMPILE_OPTIONS_ifort   "${COMPILE_OPTIONS_ifort} -ftz"                        )
+set (COMPILE_OPTIONS_ifort   "${COMPILE_OPTIONS_ifort} -assume byterecl,fpe_summary")
+set (COMPILE_OPTIONS_ifort   "${COMPILE_OPTIONS_ifort} -diag-disable 5268"          )
+set (COMPILE_OPTIONS_ifort   "${COMPILE_OPTIONS_ifort} -warn declarations"          )
+set (COMPILE_OPTIONS_ifort   "${COMPILE_OPTIONS_ifort} -warn general"               )
+set (COMPILE_OPTIONS_ifort   "${COMPILE_OPTIONS_ifort} -warn usage"                 )
+set (COMPILE_OPTIONS_ifort   "${COMPILE_OPTIONS_ifort} -warn interfaces"            )
+set (COMPILE_OPTIONS_ifort   "${COMPILE_OPTIONS_ifort} -warn ignore_loc"            )
+set (COMPILE_OPTIONS_ifort   "${COMPILE_OPTIONS_ifort} -warn alignments"            )
+set (COMPILE_OPTIONS_ifort   "${COMPILE_OPTIONS_ifort} -warn unused"                )
 
 ###################################################################################################
 # COMPILE SWITCHES FOR RUNTIME DEBUGGING
diff --git a/code/CMakeLists.txt b/code/CMakeLists.txt
index 71d373157..55bf78952 100644
--- a/code/CMakeLists.txt
+++ b/code/CMakeLists.txt
@@ -1,13 +1,47 @@
-# The dependency detection for Fortran is not working in CMake
-# Have to define them explicitly
+# The dependency detection in CMake is not functioning for Fortran
+# !!! EXPLICIT DEPENDENCY DECLARATION !!!
+###################################################################################################
+# fno-range-check:  Disable range checking on results of simplification of constant expressions during compilation
+#      -->   allows the definition of DAMASK_NaN
+#-fall-intrinsics:  all intrinsic procedures (including the GNU-specific extensions) are accepted. -Wintrinsics-std will be ignored
+#                   and no user-defined procedure with the same name as any intrinsic will be called except when it is explicitly declared external
+#      -->   allows the use of 'isnan'
+#-fno-fast-math:
+#      -->   otherwise, when setting -ffast-math, isnan always evaluates to false (I would call it a bug)
+###################################################################################################
+if (Fortran_COMPILER_NAME MATCHES "ifort.*")
+      set (SPEICAL_FLAGS "")
+elseif (Fortran_COMPILER_NAME MATCHES "gfortran.*")
+      set (SPEICAL_FLAGS "-fno-range-check -fall-intrinsics -fno-fast-math")
+else (Fortran_COMPILER_NAME MATCHES "ifort.*")
+      message (FATAL_ERROR "Unknown Fortrna compiler.")
+endif (Fortran_COMPILER_NAME MATCHES "ifort.*")
+
+set (CMAKE_Fortran_FLAGS_RELEASE "${DAMASK_Fortran_FLAGS_RELEASE} ${SPEICAL_FLAGS}")
+
 add_library(DAMASK_prec "prec.f90")
 
-###################################################################################################
+set (CMAKE_Fortran_FLAGS_RELEASE "${DAMASK_Fortran_FLAGS_RELEASE}")
 
+###################################################################################################
+# -diag-disable 7410 should disable warning about directory statement in inquire function,
+#  but does not work. hence the other 2 statements
 ###################################################################################################
 if (SPECTRAL)
+      if (Fortran_COMPILER_NAME MATCHES "ifort.*")
+            set (SPEICAL_FLAGS "-diag-remark 7410 -stand none -warn nostderrors")
+      elseif (Fortran_COMPILER_NAME MATCHES "gfortran.*")
+            set (SPEICAL_FLAGS "-fall-intrinsics")
+      else (Fortran_COMPILER_NAME MATCHES "ifort.*")
+            message (FATAL_ERROR "Unknown Fortrna compiler.")
+      endif (Fortran_COMPILER_NAME MATCHES "ifort.*")
+
+      set (CMAKE_Fortran_FLAGS_RELEASE "${DAMASK_Fortran_FLAGS_RELEASE} ${SPEICAL_FLAGS}")
+
       add_library(DAMASK_interface "spectral_interface.f90")
       target_link_libraries(DAMASK_interface DAMASK_prec)
+
+      set (CMAKE_Fortran_FLAGS_RELEASE "${DAMASK_Fortran_FLAGS_RELEASE}")
 endif(SPECTRAL)
 
 add_library(DAMASK_IO "IO.f90")