diff --git a/configure b/configure
index a0c7e1f31a2..63f30775ce2 100755
--- a/configure
+++ b/configure
@@ -843,6 +843,8 @@ PAPERCONF
 BUILD_TZONE_FALSE
 BUILD_TZONE_TRUE
 R_PROFILING
+BUILD_TRE_FALSE
+BUILD_TRE_TRUE
 BUILD_PCRE_FALSE
 BUILD_PCRE_TRUE
 BUILD_XZ_FALSE
@@ -1164,6 +1166,7 @@ with_libtiff
 with_system_zlib
 with_system_bzlib
 with_system_pcre
+with_system_tre
 with_system_xz
 with_valgrind_instrumentation
 with_internal_tzcode
@@ -1920,6 +1923,7 @@ Optional Packages:
   --with-system-zlib      use system zlib library (if available) [no]
   --with-system-bzlib     use system bzlib library (if available) [no]
   --with-system-pcre      use system PCRE library (if available) [no]
+  --with-system-tre       use system tre library (if available) [no]
   --with-system-xz        use system xz (lzma) library (if available) [yes]
   --with-valgrind-instrumentation
                           Level of additional instrumentation for Valgrind
@@ -4269,6 +4273,19 @@ else
 fi
 
 
+# Check whether --with-system-tre was given.
+if test "${with_system_tre+set}" = set; then :
+  withval=$with_system_tre; if test "${withval}" = no; then
+  use_system_tre=no
+else
+  use_system_tre=yes
+fi
+
+else
+  use_system_tre=no
+fi
+
+
 # Check whether --with-system-xz was given.
 if test "${with_system_xz+set}" = set; then :
   withval=$with_system_xz; if test "${withval}" = no; then
@@ -9049,13 +9066,13 @@ if ${lt_cv_nm_interface+:} false; then :
 else
   lt_cv_nm_interface="BSD nm"
   echo "int some_variable = 0;" > conftest.$ac_ext
-  (eval echo "\"\$as_me:9052: $ac_compile\"" >&5)
+  (eval echo "\"\$as_me:9069: $ac_compile\"" >&5)
   (eval "$ac_compile" 2>conftest.err)
   cat conftest.err >&5
-  (eval echo "\"\$as_me:9055: $NM \\\"conftest.$ac_objext\\\"\"" >&5)
+  (eval echo "\"\$as_me:9072: $NM \\\"conftest.$ac_objext\\\"\"" >&5)
   (eval "$NM \"conftest.$ac_objext\"" 2>conftest.err > conftest.out)
   cat conftest.err >&5
-  (eval echo "\"\$as_me:9058: output\"" >&5)
+  (eval echo "\"\$as_me:9075: output\"" >&5)
   cat conftest.out >&5
   if $GREP 'External.*some_variable' conftest.out > /dev/null; then
     lt_cv_nm_interface="MS dumpbin"
@@ -11903,11 +11920,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:11906: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:11923: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>conftest.err)
    ac_status=$?
    cat conftest.err >&5
-   echo "$as_me:11910: \$? = $ac_status" >&5
+   echo "$as_me:11927: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s "$ac_outfile"; then
      # The compiler can only warn and ignore the option if not recognized
      # So say no if there are warnings other than the usual output.
@@ -12242,11 +12259,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:12245: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:12262: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>conftest.err)
    ac_status=$?
    cat conftest.err >&5
-   echo "$as_me:12249: \$? = $ac_status" >&5
+   echo "$as_me:12266: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s "$ac_outfile"; then
      # The compiler can only warn and ignore the option if not recognized
      # So say no if there are warnings other than the usual output.
@@ -12347,11 +12364,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:12350: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:12367: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>out/conftest.err)
    ac_status=$?
    cat out/conftest.err >&5
-   echo "$as_me:12354: \$? = $ac_status" >&5
+   echo "$as_me:12371: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s out/conftest2.$ac_objext
    then
      # The compiler can only warn and ignore the option if not recognized
@@ -12402,11 +12419,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:12405: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:12422: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>out/conftest.err)
    ac_status=$?
    cat out/conftest.err >&5
-   echo "$as_me:12409: \$? = $ac_status" >&5
+   echo "$as_me:12426: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s out/conftest2.$ac_objext
    then
      # The compiler can only warn and ignore the option if not recognized
@@ -14769,7 +14786,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 14772 "configure"
+#line 14789 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -14865,7 +14882,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 14868 "configure"
+#line 14885 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -16814,11 +16831,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:16817: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:16834: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>conftest.err)
    ac_status=$?
    cat conftest.err >&5
-   echo "$as_me:16821: \$? = $ac_status" >&5
+   echo "$as_me:16838: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s "$ac_outfile"; then
      # The compiler can only warn and ignore the option if not recognized
      # So say no if there are warnings other than the usual output.
@@ -16913,11 +16930,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:16916: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:16933: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>out/conftest.err)
    ac_status=$?
    cat out/conftest.err >&5
-   echo "$as_me:16920: \$? = $ac_status" >&5
+   echo "$as_me:16937: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s out/conftest2.$ac_objext
    then
      # The compiler can only warn and ignore the option if not recognized
@@ -16965,11 +16982,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:16968: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:16985: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>out/conftest.err)
    ac_status=$?
    cat out/conftest.err >&5
-   echo "$as_me:16972: \$? = $ac_status" >&5
+   echo "$as_me:16989: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s out/conftest2.$ac_objext
    then
      # The compiler can only warn and ignore the option if not recognized
@@ -18345,11 +18362,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:18348: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:18365: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>conftest.err)
    ac_status=$?
    cat conftest.err >&5
-   echo "$as_me:18352: \$? = $ac_status" >&5
+   echo "$as_me:18369: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s "$ac_outfile"; then
      # The compiler can only warn and ignore the option if not recognized
      # So say no if there are warnings other than the usual output.
@@ -18444,11 +18461,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:18447: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:18464: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>out/conftest.err)
    ac_status=$?
    cat out/conftest.err >&5
-   echo "$as_me:18451: \$? = $ac_status" >&5
+   echo "$as_me:18468: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s out/conftest2.$ac_objext
    then
      # The compiler can only warn and ignore the option if not recognized
@@ -18496,11 +18513,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:18499: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:18516: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>out/conftest.err)
    ac_status=$?
    cat out/conftest.err >&5
-   echo "$as_me:18503: \$? = $ac_status" >&5
+   echo "$as_me:18520: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s out/conftest2.$ac_objext
    then
      # The compiler can only warn and ignore the option if not recognized
@@ -23190,7 +23207,7 @@ _ACEOF
 # flags.
 r_save_CFLAGS=$CFLAGS
 CFLAGS="$CFLAGS $r_verb"
-(eval echo $as_me:23193: \"$ac_link\") >&5
+(eval echo $as_me:23210: \"$ac_link\") >&5
 r_c_v_output=`eval $ac_link 5>&1 2>&1 | grep -v 'Driving:'`
 echo "$r_c_v_output" >&5
 CFLAGS=$r_save_CFLAGS
@@ -23265,7 +23282,7 @@ _ACEOF
 # flags.
 r_save_CFLAGS=$CFLAGS
 CFLAGS="$CFLAGS $r_cv_prog_c_v"
-(eval echo $as_me:23268: \"$ac_link\") >&5
+(eval echo $as_me:23285: \"$ac_link\") >&5
 r_c_v_output=`eval $ac_link 5>&1 2>&1 | grep -v 'Driving:'`
 echo "$r_c_v_output" >&5
 CFLAGS=$r_save_CFLAGS
@@ -34390,6 +34407,93 @@ fi
 
 
 
+## tre headers and libraries.
+if test "x${use_system_tre}" = xyes; then
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for tre_regncompb in -ltre" >&5
+$as_echo_n "checking for tre_regncompb in -ltre... " >&6; }
+if ${ac_cv_lib_tre_tre_regncompb+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  ac_check_lib_save_LIBS=$LIBS
+LIBS="-ltre  $LIBS"
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+/* Override any GCC internal prototype to avoid an error.
+   Use char because int might match the return type of a GCC
+   builtin and then its argument prototype would still apply.  */
+#ifdef __cplusplus
+extern "C"
+#endif
+char tre_regncompb ();
+#ifdef F77_DUMMY_MAIN
+
+#  ifdef __cplusplus
+     extern "C"
+#  endif
+   int F77_DUMMY_MAIN() { return 1; }
+
+#endif
+int
+main ()
+{
+return tre_regncompb ();
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_link "$LINENO"; then :
+  ac_cv_lib_tre_tre_regncompb=yes
+else
+  ac_cv_lib_tre_tre_regncompb=no
+fi
+rm -f core conftest.err conftest.$ac_objext \
+    conftest$ac_exeext conftest.$ac_ext
+LIBS=$ac_check_lib_save_LIBS
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_tre_tre_regncompb" >&5
+$as_echo "$ac_cv_lib_tre_tre_regncompb" >&6; }
+if test "x$ac_cv_lib_tre_tre_regncompb" = xyes; then :
+  have_tre=yes
+else
+  have_tre=no
+fi
+
+  if test "${have_tre}" = yes; then
+    for ac_header in tre/tre.h
+do :
+  ac_fn_c_check_header_mongrel "$LINENO" "tre/tre.h" "ac_cv_header_tre_tre_h" "$ac_includes_default"
+if test "x$ac_cv_header_tre_tre_h" = xyes; then :
+  cat >>confdefs.h <<_ACEOF
+#define HAVE_TRE_TRE_H 1
+_ACEOF
+ have_tre=yes
+else
+  have_tre=no
+fi
+
+done
+
+  fi
+if test "x${have_tre}" = xyes; then
+
+$as_echo "#define HAVE_TRE 1" >>confdefs.h
+
+  LIBS="-ltre ${LIBS}"
+fi
+else
+  have_tre="no"
+fi
+ if test x${have_tre} != xyes; then
+  BUILD_TRE_TRUE=
+  BUILD_TRE_FALSE='#'
+else
+  BUILD_TRE_TRUE='#'
+  BUILD_TRE_FALSE=
+fi
+
+
+
 ## POSIX times.
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether leap seconds are treated according to POSIX" >&5
 $as_echo_n "checking whether leap seconds are treated according to POSIX... " >&6; }
@@ -36217,11 +36321,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:36220: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:36324: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>conftest.err)
    ac_status=$?
    cat conftest.err >&5
-   echo "$as_me:36224: \$? = $ac_status" >&5
+   echo "$as_me:36328: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s "$ac_outfile"; then
      # The compiler can only warn and ignore the option if not recognized
      # So say no if there are warnings other than the usual output.
@@ -36316,11 +36420,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:36319: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:36423: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>out/conftest.err)
    ac_status=$?
    cat out/conftest.err >&5
-   echo "$as_me:36323: \$? = $ac_status" >&5
+   echo "$as_me:36427: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s out/conftest2.$ac_objext
    then
      # The compiler can only warn and ignore the option if not recognized
@@ -36368,11 +36472,11 @@ else
    -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
    -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
    -e 's:$: $lt_compiler_flag:'`
-   (eval echo "\"\$as_me:36371: $lt_compile\"" >&5)
+   (eval echo "\"\$as_me:36475: $lt_compile\"" >&5)
    (eval "$lt_compile" 2>out/conftest.err)
    ac_status=$?
    cat out/conftest.err >&5
-   echo "$as_me:36375: \$? = $ac_status" >&5
+   echo "$as_me:36479: \$? = $ac_status" >&5
    if (exit $ac_status) && test -s out/conftest2.$ac_objext
    then
      # The compiler can only warn and ignore the option if not recognized
@@ -42774,6 +42878,10 @@ if test -z "${BUILD_PCRE_TRUE}" && test -z "${BUILD_PCRE_FALSE}"; then
   as_fn_error $? "conditional \"BUILD_PCRE\" was never defined.
 Usually this means the macro was only invoked conditionally." "$LINENO" 5
 fi
+if test -z "${BUILD_TRE_TRUE}" && test -z "${BUILD_TRE_FALSE}"; then
+  as_fn_error $? "conditional \"BUILD_TRE\" was never defined.
+Usually this means the macro was only invoked conditionally." "$LINENO" 5
+fi
 if test -z "${BUILD_TZONE_TRUE}" && test -z "${BUILD_TZONE_FALSE}"; then
   as_fn_error $? "conditional \"BUILD_TZONE\" was never defined.
 Usually this means the macro was only invoked conditionally." "$LINENO" 5
diff --git a/configure.ac b/configure.ac
index 52c17ffe906..4a81414ffd9 100644
--- a/configure.ac
+++ b/configure.ac
@@ -420,6 +420,10 @@ AC_ARG_WITH([system-pcre],
 [AS_HELP_STRING([--with-system-pcre],[use system PCRE library (if available) @<:@no@:>@])],
 [R_ARG_USE_SYSTEM(pcre)],
 [use_system_pcre=no])
+AC_ARG_WITH([system-tre],
+[AS_HELP_STRING([--with-system-tre],[use system tre library (if available) @<:@no@:>@])],
+[R_ARG_USE_SYSTEM(tre)],
+[use_system_tre=no])
 AC_ARG_WITH([system-xz],
 [AS_HELP_STRING([--with-system-xz],[use system xz (lzma) library (if available) @<:@yes@:>@])],
 [R_ARG_USE_SYSTEM(xz)],
@@ -2286,6 +2290,9 @@ R_LZMA
 ## PCRE headers and libraries.
 R_PCRE
 
+## tre headers and libraries.
+R_TRE
+
 ## POSIX times.
 R_SYS_POSIX_LEAPSECONDS
 
diff --git a/doc/NEWS.Rd b/doc/NEWS.Rd
index 314bed1ebfd..03185d6b48b 100644
--- a/doc/NEWS.Rd
+++ b/doc/NEWS.Rd
@@ -287,6 +287,10 @@
       counting instead of the \code{NAMED} mechanism by defining
       \code{SWITCH_TO_REFCNT} in \file{Rinternals.h}. This may become
       the default in the future.
+      
+      \item There is a new option \option{--use-system-tre} to use a
+      suitable system \pkg{tre} library: at present this means a version
+      from their \command{git} repository.
     }
   }
 
diff --git a/doc/manual/R-admin.texi b/doc/manual/R-admin.texi
index 02ae445d9c4..7b114481a96 100644
--- a/doc/manual/R-admin.texi
+++ b/doc/manual/R-admin.texi
@@ -3063,6 +3063,10 @@ is assumed by some @R{} packages. Neither are tested by
 compiled in.  As the latter suffice and are tested with @R{} you should
 not need to change this.
 
+Option @option{--with-system-tre} is also available: it needs a recent
+version of TRE (currently only from the @command{git} repository at
+@url{https://github.com/laurikari/tre/}).
+
 @code{liblzma} from @code{xz-utils} version 5.0.3 or later will be used
 if installed: the version in the @R{} sources can be selected instead by
 configuring with @option{--with-system-xz=no}.  Systems differ in what
diff --git a/m4/R.m4 b/m4/R.m4
index dbaff680d33..8e50b316a5c 100644
--- a/m4/R.m4
+++ b/m4/R.m4
@@ -3156,6 +3156,26 @@ fi
 AM_CONDITIONAL(BUILD_BZLIB, [test "x${have_bzlib}" = xno])
 ])# R_BZLIB
 
+## R_TRE
+## -------
+## Try finding tre library and headers.
+## We check that both are installed,
+AC_DEFUN([R_TRE],
+[if test "x${use_system_tre}" = xyes; then
+  AC_CHECK_LIB(tre, tre_regncompb, [have_tre=yes], [have_tre=no])
+  if test "${have_tre}" = yes; then
+    AC_CHECK_HEADERS(tre/tre.h, [have_tre=yes], [have_tre=no])
+  fi
+if test "x${have_tre}" = xyes; then
+  AC_DEFINE(HAVE_TRE, 1, [Define if your system has tre.])
+  LIBS="-ltre ${LIBS}"
+fi
+else
+  have_tre="no"
+fi
+AM_CONDITIONAL(BUILD_TRE, [test x${have_tre} != xyes])
+])# R_TRE
+
 ## R_LZMA
 ## -------
 ## Try finding liblzma library and headers.
diff --git a/src/extra/Makefile.in b/src/extra/Makefile.in
index 35d5e951836..f27fd5975ff 100644
--- a/src/extra/Makefile.in
+++ b/src/extra/Makefile.in
@@ -22,7 +22,7 @@ LIBPCRE =@BUILD_PCRE_TRUE@ make.pcre
 LIBZ =@BUILD_ZLIB_TRUE@ make.zlib
 LIBXDR =@BUILD_XDR_TRUE@ make.xdr
 LIBINTL =@BUILD_LIBINTL_TRUE@ make.intl
-LIBTRE = make.tre
+LIBTRE =@BUILD_TRE_TRUE@ make.tre
 LIBTZONE = @BUILD_TZONE_TRUE@make.tzone
 LIBXZ =@BUILD_XZ_TRUE@ make.xz
 EXTRAS = $(RBLAS) $(LIBBZ2) $(LIBPCRE) $(LIBZ) $(LIBXDR) $(LIBINTL) \
diff --git a/src/extra/tre/Makefile.in b/src/extra/tre/Makefile.in
index 10a15c2154f..a5fab6da3cd 100644
--- a/src/extra/tre/Makefile.in
+++ b/src/extra/tre/Makefile.in
@@ -33,7 +33,7 @@ libtre_a_SOURCES = $(SOURCES)
 libtre_a_OBJECTS = $(OBJECTS)
 
 
-all: R
+all: @BUILD_TRE_TRUE@ R
 
 Makefile: $(srcdir)/Makefile.in \
   $(top_builddir)/config.status \
@@ -44,9 +44,9 @@ Makedeps: Makefile $(DEPENDS)
 	@cat $(DEPENDS) >> Makefile
 	@touch $@
 
-R: Makefile
-	@$(MAKE) Makedeps
-	@$(MAKE) $(noinst_LIBRARIES)
+R: Makefile @BUILD_TRE_TRUE@
+	@BUILD_TRE_TRUE@ @$(MAKE) Makedeps
+	@BUILD_TRE_TRUE@ @$(MAKE) $(noinst_LIBRARIES)
 
 libtre.a: $(libtre_a_OBJECTS)
 	rm -f $@
diff --git a/src/include/config.h.in b/src/include/config.h.in
index 1f0459c0a62..7a1555c228d 100644
--- a/src/include/config.h.in
+++ b/src/include/config.h.in
@@ -789,6 +789,12 @@
 /* Define to 1 if your 'struct tm' has tm_zone. */
 #undef HAVE_TM_ZONE
 
+/* Define if your system has tre. */
+#undef HAVE_TRE
+
+/* Define to 1 if you have the <tre/tre.h> header file. */
+#undef HAVE_TRE_TRE_H
+
 /* Define to 1 if you have the `tsearch' function. */
 #undef HAVE_TSEARCH
 
diff --git a/src/main/Makefile.in b/src/main/Makefile.in
index b4d19a5678f..e2a956c416c 100644
--- a/src/main/Makefile.in
+++ b/src/main/Makefile.in
@@ -71,7 +71,7 @@ DISTFILES = Makefile.in Makefile.win \
 ZLIB_CPPFLAGS = @BUILD_ZLIB_TRUE@ -I$(top_srcdir)/src/extra/zlib
 BZLIB_CPPFLAGS = @BUILD_BZLIB_TRUE@ -I$(top_srcdir)/src/extra/bzip2
 PCRE_CPPFLAGS = @BUILD_PCRE_TRUE@ -I$(top_srcdir)/src/extra/pcre
-TRE_CPPFLAGS = -I$(top_srcdir)/src/extra
+TRE_CPPFLAGS = @BUILD_TRE_TRUE@ -I$(top_srcdir)/src/extra
 XDR_CPPFLAGS = @BUILD_XDR_TRUE@ -I$(top_srcdir)/src/extra/xdr
 @BUILD_XDR_FALSE@XDR_CPPFLAGS = @TIRPC_CPPFLAGS@
 XZ_CPPFLAGS = @BUILD_XZ_TRUE@  -I$(top_srcdir)/src/extra/xz/api
@@ -86,7 +86,7 @@ ALL_CPPFLAGS = $(ZLIB_CPPFLAGS) $(BZLIB_CPPFLAGS) $(PCRE_CPPFLAGS) \
 R_ZLIBS = @BUILD_ZLIB_TRUE@ ../extra/zlib/libz.a
 R_BZLIBS = @BUILD_BZLIB_TRUE@ ../extra/bzip2/libbz2.a
 R_PCRE = @BUILD_PCRE_TRUE@ ../extra/pcre/libpcre.a
-R_TRE = ../extra/tre/libtre.a
+R_TRE = @BUILD_TRE_TRUE@ ../extra/tre/libtre.a
 R_XDR = @BUILD_XDR_TRUE@ ../extra/xdr/libxdr.a
 R_XZ = @BUILD_XZ_TRUE@  ../extra/xz/liblzma.a
 R_LIBINTL = @BUILD_LIBINTL_TRUE@ ../extra/intl/libintl.a