diff --git a/.travis.yml b/.travis.yml
index 6edea7a0..4c2e095d 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -547,4 +547,4 @@ install:
 script:
   - |-
     echo "using $TOOLSET : : $COMPILER : <cxxflags>-std=$CXXSTD ;" > ~/user-config.jam
-  - ./b2 libs/fusion/test toolset=$TOOLSET
+  - ./b2 libs/fusion/test toolset=$TOOLSET define=RUNNING_ON_TRAVIS=1
diff --git a/appveyor.yml b/appveyor.yml
index 82c1bedf..ba83a8c1 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -71,4 +71,4 @@ install:
 build: off
 
 test_script:
-  - b2 libs/fusion/test toolset=%TOOLSET%
+  - b2 libs/fusion/test toolset=%TOOLSET% define=RUNNING_ON_APPVEYOR=1