deny compiler warnings in CI (#2570)

.gitlab-ci.yml

@@ -5,6 +5,7 @@ variables:
   GIT_DEPTH: "3"
   SIMPLECOV: "true"
   RUST_BACKTRACE: "1"
+  RUSTFLAGS: "-D warnings"
 cache:
   key: "$CI_BUILD_NAME/$CI_BUILD_REF_NAME"
   untracked: true
@@ -264,7 +265,7 @@ windows:
     - set INCLUDE=C:\Program Files (x86)\Microsoft SDKs\Windows\v7.1A\Include;C:\vs2015\VC\include;C:\Program Files (x86)\Windows Kits\10\Include\10.0.10240.0\ucrt
     - set LIB=C:\vs2015\VC\lib;C:\Program Files (x86)\Windows Kits\10\Lib\10.0.10240.0\ucrt\x64
     - set RUST_BACKTRACE=1
-    - set RUSTFLAGS=-Zorbit=off
+    - set RUSTFLAGS=%RUSTFLAGS% -Zorbit=off
     - rustup default stable-x86_64-pc-windows-msvc
     - cargo build --release --verbose
     - cmd md5sum target\release\parity >> checksum

.travis.yml

@@ -31,6 +31,7 @@ env:
   - RUN_COVERAGE="false"
   - RUN_DOCS="false"
   - TEST_OPTIONS=""
+  - RUSTFLAGS="-D warnings"
   # GH_TOKEN for documentation
   - secure: 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
   - KCOV_CMD="./kcov-master/tmp/usr/local/bin/kcov"

appveyor.yml

@@ -6,7 +6,7 @@ environment:
   certpass:
     secure: 0BgXJqxq9Ei34/hZ7121FQ==
   keyfile: C:\users\appveyor\Certificates.p12
-  RUSTFLAGS: -Zorbit=off
+  RUSTFLAGS: -Zorbit=off -D warnings
 
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