With today's CVS, on NetBSD-current/i386, gmake 3.79.1 just 1 test failed:
PASS: mdemo2-conf.test
=== Running mdemo2-make.test
= Running `gmake ' in mdemo2
gmake[2]: Entering directory `/usr/src/local/libtool/tests/mdemo2'
gcc -DPACKAGE_NAME=\"mdemo2\" -DPACKAGE_TARNAME=\"mdemo2\" -DPACKAGE_VERSION=\"0.1\" -DPACKAGE_STRING=\"mdemo2\
0.1\" -DPACKAGE_BUGREPORT=\"address@hidden" -DPACKAGE=\"mdemo2\" -DVERSION=\"0.1\" -DSTDC_HEADERS=1
-DHAVE_SYS_TYPES_H=1 -DHAVE_SYS_STAT_H=1 -DHAVE_STDLIB_H=1 -DHAVE_STRING_H=1 -DHAVE_MEMORY_H=1 -DHAVE_STRINGS_H=1 -DHAVE_INTTYPES_H=1
-DHAVE_STDINT_H=1 -DHAVE_UNISTD_H=1 -DHAVE_DLFCN_H=1 -I. -I/usr/src/local/libtool/tests/mdemo2 -Imdemo2-0.1/libltdl -g -O2 -c main.c
main.c:22:18: ltdl.h: No such file or directory
gmake[2]: *** [main.o] Error 1
gmake[2]: Leaving directory `/usr/src/local/libtool/tests/mdemo2'
FAIL: mdemo2-make.test
So, which file is ./libtool looking for?