Travis: create configure flags once, then echo the flags

Creating the configure flags once avoids inconsistent flags
between configure and distcheck configure.

Echoing the flags helps developers work out what configure is
doing.

(Backported to 0.2.9 and later as a precaution.)

Fixes 27088 on 0.3.4.1-alpha, adds logging in previous releases.

.travis.yml

@@ -108,10 +108,12 @@ install:
 
 script:
   - ./autogen.sh
-  - ./configure $COVERAGE_OPTIONS  $HARDENING_OPTIONS --disable-asciidoc --enable-fatal-warnings --disable-silent-rules
+  - CONFIGURE_FLAGS="$COVERAGE_OPTIONS  $HARDENING_OPTIONS --disable-asciidoc --enable-fatal-warnings --disable-silent-rules"
+  - echo $CONFIGURE_FLAGS
+  - ./configure $CONFIGURE_FLAGS
   ## We run `make check` because that's what https://jenkins.torproject.org does.
   - if [[ "$DISTCHECK" == "" ]]; then make check; fi
-  - if [[ "$DISTCHECK" != "" ]]; then make distcheck DISTCHECK_CONFIGURE_FLAGS="$HARDENING_OPTIONS $COVERAGE_OPTIONS --disable-asciidoc --enable-fatal-warnings --disable-silent-rules"; fi
+  - if [[ "$DISTCHECK" != "" ]]; then make distcheck DISTCHECK_CONFIGURE_FLAGS="$CONFIGURE_FLAGS"; fi
 
 after_failure:
   ## configure will leave a log file with more details of config failures.

changes/bug27088

@@ -0,0 +1,5 @@
+  o Minor bugfixes (continuous integration):
+    - Pass the module flags to distcheck configure, and
+      log the flags before running configure. (Backported
+      to 0.2.9 and later as a precaution.)
+      Fixes bug 27088; bugfix on 0.3.4.1-alpha.