.travis.yml: Enable ASAN

.travis.yml

@@ -1,4 +1,8 @@
 language: c
+sudo: required
+
+env:
+  - XCFLAGS="-g -fsanitize=address" XLDFLAGS=-fsanitize=address ASAN_OPTIONS=detect_leaks=0
 
 install:
   - curl https://sh.rustup.rs -sSf | sh -s -- -y
@@ -14,20 +18,17 @@ compiler:
 
 matrix:
   fast_finish: true
-  allow_failures:
-    # TODO: determine why clang build of "ristretto_gen_tables" SEGVs sporadically
-    # https://github.com/Ristretto/libristretto255/issues/24
-    - os: linux
-      compiler: clang
   include:
     # TODO: test (instead of just build) on OS X
     # https://github.com/Ristretto/libristretto255/issues/19
     - os: osx
       compiler: clang
+      env: []
       install: ""
       script: make
     - os: osx
       compiler: gcc
+      env: []
       install: ""
       script: make