Add manual override for FORTRANUNDERSCORE

ParLib.src/CMakeLists.txt

@@ -81,11 +81,17 @@ endif(BUILD_STATIC_LIBS)
 
 if( BUILD_FORT_LIBS )
 if(BUILD_STATIC_LIBS)
+    if(FORTRANUNDERSCORE)
+        add_definitions(-DFORTRANUNDERSCORE)
+    elseif(FORTRANDOUBLEUNDERSCORE)
+        add_definitions(-DFORTRANDOUBLEUNDERSCORE)
+    else()
     include(FortranCInterface)
     FortranCInterface_VERIFY()
     FortranCInterface_HEADER(${CMAKE_CURRENT_SOURCE_DIR}/FC.h MACRO_NAMESPACE "FC_")
     message(STATUS "FORTRAN_C_INTEFACE TEST:    ${FortranCInterface_VERIFIED_C}")
     add_definitions(-DFC_MANGLE=1)
+    endif()
     add_library(parlibf-static STATIC "")
     target_sources( parlibf-static
             PRIVATE

ParLib.src/parlibf.c

 #include <stdlib.h>
 #include "parlib.h"
+#ifdef FC_MANGLE
 # include "FC.h"
+#endif
 // ParLib v1.8 initialization
 // -------------------------------------------------------------------------- //
 #ifdef FORTRANUNDERSCORE