Files:
tests/test-tsearch.sh
tests/test-tsearch.c
tests/signature.h

Depends-on:
stdint

configure.ac:
TEST_TSEARCH_LIBM=
AC_TRY_LINK([
   #ifndef __NO_MATH_INLINES
   # define __NO_MATH_INLINES 1 /* for glibc */
   #endif
   #include <math.h>
   double x;],
  [x = log (x);], , [TEST_TSEARCH_LIBM=-lm])
AC_SUBST([TEST_TSEARCH_LIBM])
AC_CHECK_FUNCS_ONCE([initstate])

Makefile.am:
TESTS += test-tsearch.sh
check_PROGRAMS += test-tsearch
test_tsearch_LDADD = $(LDADD) @TEST_TSEARCH_LIBM@