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

Depends-on:
stdint

configure.ac:
TEST_TSEARCH_LIBM=
AC_LINK_IFELSE(
  [AC_LANG_PROGRAM(
     [[#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@