Merge pull request #157 from rtburns-jpl/gfortran10

Add argument mismatch workaround for gfortran 10

.cmake/isce2_buildflags.cmake

@@ -8,6 +8,11 @@ add_compile_options(
     $<$<COMPILE_LANGUAGE:Fortran>:-ffixed-line-length-none>
     $<$<COMPILE_LANGUAGE:Fortran>:-fno-range-check>
     $<$<COMPILE_LANGUAGE:Fortran>:-fno-second-underscore>)
+if(CMAKE_Fortran_COMPILER_ID STREQUAL "GNU" AND
+   CMAKE_Fortran_COMPILER_VERSION VERSION_GREATER_EQUAL 10)
+    add_compile_options(
+        $<$<COMPILE_LANGUAGE:Fortran>:-fallow-argument-mismatch>)
+endif()
 
 # Set up build flags for C++ and Fortran.
 set(CMAKE_CXX_STANDARD 11)