travis: Use -O3 option (GH-5599)

We don't use debugger on Travis..
(cherry picked from commit 8ff53564730f7ba503f5ad94418c309c48e8516d)

Co-authored-by: INADA Naoki <methane@users.noreply.github.com>

diff --git a/.travis.yml b/.travis.yml
index 7d92c2e2f852986cb5006a74f4ecedc45f03cb96..2ced4d0b97f6f84da251b2e5a6c2cfd2bc95cf29 100644 (file)
--- a/.travis.yml
+++ b/.travis.yml
@@ -8,6 +8,11 @@ cache:
   - pip
   - ccache
 
+env:
+  global:
+    # Use -O3 because we don't use debugger on Travis-CI
+    - CFLAGS="-O3"
+
 branches:
   only:
     - master