diff --git a/.travis.yml b/.travis.yml
index e079cfc..fc9ef29 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -264,7 +264,7 @@ install:
 script:
   - |-
     echo "using $TOOLSET : : $COMPILER ;" > ~/user-config.jam
-  - ./b2 -j3 libs/system/test toolset=$TOOLSET cxxstd=$CXXSTD ${UBSAN:+cxxflags=-fsanitize=undefined} ${UBSAN:+cxxflags=-fno-sanitize-recover=undefined} ${UBSAN:+linkflags=-fsanitize=undefined} ${UBSAN:+define=UBSAN=1}
+  - ./b2 -j3 libs/system/test toolset=$TOOLSET cxxstd=$CXXSTD variant=debug,release ${UBSAN:+cxxflags=-fsanitize=undefined} ${UBSAN:+cxxflags=-fno-sanitize-recover=undefined} ${UBSAN:+linkflags=-fsanitize=undefined} ${UBSAN:+define=UBSAN=1}
 
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