Clean-up and gitignore a.out.

.gitignore

@@ -41,6 +41,7 @@ Makefile
 Doxyfile
 stamp-h1
 stamp-h2
+a.out
 
 # Common files created by make
 

configure.ac

@@ -21,6 +21,8 @@ AM_EXTRA_RECURSIVE_TARGETS([doc])
 AC_CONFIG_SRCDIR([src/sct_reporter.c])
 
 LT_INIT([pic-only])
+dnl Clean up after Libtool checks for C compiler:
+rm -f a.out
 
 #
 # information on the package
@@ -171,6 +173,8 @@ AX_PROG_CC_MPI([test x"$mpi" != xfalse],
                 fi])
 
 AC_PROG_FC
+dnl Clean up after Libtool checks for Fortran compiler:
+rm -f a.out
 AX_PROG_FC_MPI([test x"$mpi" != xfalse],
                [],
                [if test x"$mpi" = xtrue; then