Increase stack size on ci

This is required for tests/target/issue-3465.rs.

Author: topecongiro

.travis.yml

@@ -45,7 +45,7 @@ script:
   - |
     if [ -z ${INTEGRATION} ]; then
       cargo build
-      cargo test
+      RUST_MIN_STACK=8388608 cargo test
     else
       ./ci/integration.sh
     fi

appveyor.yml

@@ -2,6 +2,7 @@
 # and modified (mainly removal of deployment) to suit rustfmt.
 
 environment:
+  RUST_MIN_STACK: 8388608
   global:
     PROJECT_NAME: rustfmt
   matrix: