Travis tests: compile with verbose flag using both clang and gcc

Use preconfigured make config to avoid warnings when autoconf is not
used. This also fixes error emitted by `git describe` because the tags
are not available in the cloned repository.

.travis.yml

@@ -1,13 +1,18 @@
 language: c
 
+compiler:
+  - clang
+  - gcc
+
 env:
-  - TEST=autoconf
-  - TEST=make
+  - TEST=autoconf VERBOSE=1
+  - TEST=make     VERBOSE=@
 
 before_install: sudo apt-get update -qq
 
 install: sudo apt-get install -qq --no-install-recommends asciidoc xmlto docbook-utils
 
 script:
-  - if [ x"$TEST" = xautoconf ]; then ./autogen.sh && ./configure; fi
-  - make && make doc test && sudo make install install-doc
+  - if [ "$TEST" = autoconf ]; then ./autogen.sh && ./configure; fi
+  - if [ "$TEST" = make ]; then cp contrib/config.make .; fi
+  - make V=$VERBOSE DESTDIR=/tmp all test install install-doc

Makefile

@@ -22,9 +22,10 @@ mandir ?= $(datarootdir)/man
 # DESTDIR=
 
 ifneq (,$(wildcard .git))
-GITDESC	= $(subst tig-,,$(shell git describe))
+GITDESC	= $(subst tig-,,$(shell git describe 2>/dev/null))
+COMMIT := $(if $(GITDESC),$(GITDESC),$(VERSION)-g$(shell git describe --always))
 WTDIRTY	= $(if $(shell git diff-index HEAD 2>/dev/null),-dirty)
-VERSION	= $(GITDESC)$(WTDIRTY)
+VERSION	= $(COMMIT)$(WTDIRTY)
 endif
 ifdef DIST_VERSION
 VERSION = $(DIST_VERSION)