build: do not hardcode cpp invocation

This needs to be overridable by using $(CPP) instead. Patch from
Patrick McLean (Sony Interactive Entertainment Inc).

diff --git a/src/daemon/Makefile.am b/src/daemon/Makefile.am
index 0d5f2f375e725d3ea9c47c569faa4a504a935e74..cc41a8a151d8692dfae42ca2a1403e064ea8c088 100644 (file)
--- a/src/daemon/Makefile.am
+++ b/src/daemon/Makefile.am
@@ -108,7 +108,7 @@ CLEANFILES    += syscall-names.h
 syscall-names.h:
        $(AM_V_GEN)
        $(AM_V_at)echo "static const char *syscall_names[] = {" > $@ ;\
-       echo "#include <sys/syscall.h>" | cpp -dM | grep '^#define __NR_' | \
+       echo "#include <sys/syscall.h>" | $(CPP) -dM | grep '^#define __NR_' | \
                LC_ALL=C sed -r -n -e 's/^\#define[ \t]+__NR_([a-z0-9_]+)[ \t]+([0-9]+)(.*)/ [\2] = "\1",/p' >> $@ ;\
        echo "};" >> $@
 nodist_liblldpd_la_SOURCES += syscall-names.h