Hi Bruno, Kiyoshi helped tracking this down. In particular this trace:
> $ make V=1 < /dev/null > rm -f examples/c/reccalc/scan.stamp examples/c/reccalc/scan.stamp.tmp > /opt/GNU_Buildutils/coreutils/bin/mkdir -p examples/c/reccalc > touch examples/c/reccalc/scan.stamp.tmp > flex -o examples/c/reccalc/scan.c --header-file=examples/c/reccalc/scan.h > <stdin>:1: premature EOF > *** Error code 1 > make: Fatal error: Command failed for target `examples/c/reccalc/scan.stamp' allowed to spot the problem: the use of $< in that rule, which is not a pattern rule (so $< expands to nothing). This was addressed here: https://lists.gnu.org/archive/html/bison-patches/2019-05/msg00017.html and I submitted a syntax-check for that to gnulib here: https://lists.gnu.org/archive/html/bug-gnulib/2019-05/msg00095.html Cheers!
