Detects "underscore" in name-mangling scheme

configure.ac

@@ -6,17 +6,21 @@ AM_INIT_AUTOMAKE
 
 AC_CONFIG_SRCDIR([Nek5000/core/drive1.f])
 
+###############################################################################
+# BUILT-IN CHECKS
+###############################################################################
+
 # C compiler checks
 AC_PROG_CC
 AC_PROG_CC_C_O
-AC_CHECK_SIZEOF([int *])    # Get sizeof int*, set SIZEOF_INT_P
+AC_CHECK_SIZEOF([int *])    # Get sizeof int*, set SIZEOF_INT_P. If SIZEOF_INT_P == 8, then Nek needs -DPTRSIZE8
 AC_CHECK_SIZEOF([long int]) # Get sizeof long int, set SIZEOF_LONG_INT
 
 # F77 compiler checks
 AC_PROG_F77             # Validate F77 compiler
 AC_PROG_F77_C_O         # Necessary for automake
 AC_F77_LIBRARY_LDFLAGS  # Determine -l and -L flags, append to $FLIBS
-AC_F77_WRAPPERS         # Discover how to call F77 funcs from C, set F77_FUNC macro
+AC_F77_WRAPPERS         # Discover how to call F77 funcs from C, set F77_FUNC macro.  If underscore, then Nek needs -DUNDERSCORE
 
 # Discover flags for Fortran preprocessing
 FC_temp="$F77"; FC="$F77"
@@ -24,6 +28,15 @@ AC_FC_PP_SRCEXT([f])
 AC_FC_PP_DEFINE
 FC="$FC_temp"
 
+###############################################################################
+# USER-DEFINED CHECKS
+###############################################################################
+
+# See if underscore is in mangling scheme
+if echo "foobar"| tr -d @<:@:blank:@:>@ | grep '\<underscore\>' > /dev/null ; then 
+  # TODO: Add UNDERSCORE to Nek's PPLIST
+  echo "GOT IT"; 
+fi
 
 AC_ARG_ENABLE([timer],
               [AS_HELP_STRING([--disable-timer], [disable runtime statistics @<:@default: enabled@:>@])],
@@ -69,4 +82,5 @@ AC_ARG_ENABLE([extbar],
               [AS_HELP_STRING([--enable-extbar], [adds underscore to exit call(for BGQ) @<:@default: disabled@:>@])],
               [extbar=${enableval}], [extbar=no])
 
+
 AC_OUTPUT