Fix AVX/AVX2 issues with prebuilt ponyc

We regularly get issues opened from people having problems
with the prebuilt pony packages where their platform
doesn't support AVX or AVX2 and the prebuilt packages were
built with that on.

This commit should get us building with the simplest of baselines
for users and allow them to run without issue.

The `arch=` idea is Sylvan's.

.travis.yml

@@ -230,7 +230,7 @@ after_success:
           PACKAGE_CONFLICTS="ponyc-release";
       fi;
       PACKAGE_ITERATION="${PACKAGE_ITERATION}${TRAVIS_BUILD_NUMBER}.`git rev-parse --short --verify HEAD^{commit}`";
-      make verbose=1 config=release package_name="$PACKAGE_NAME" package_conflicts="$PACKAGE_CONFLICTS" package_base_version="`cat VERSION`" package_iteration="$PACKAGE_ITERATION" deploy && export UPLOAD=yes;
+      make verbose=1 arch= config=release package_name="$PACKAGE_NAME" package_conflicts="$PACKAGE_CONFLICTS" package_base_version="`cat VERSION`" package_iteration="$PACKAGE_ITERATION" deploy && export UPLOAD=yes;
     fi;
 
   # For a release release build with the latest stable LLVM, upload docs.

Dockerfile

@@ -24,7 +24,7 @@ COPY lib      /src/ponyc/lib
 COPY test     /src/ponyc/test
 COPY packages /src/ponyc/packages
 
-RUN make \
+RUN make -arch= \
  && make install \
  && rm -rf /src/ponyc/build
 

README.md

@@ -61,6 +61,9 @@ docker run -v /path/to/my-code:/src/main ponylang/ponyc ./main
 
 If you're using `docker-machine` instead of native docker, make sure you aren't using [an incompatible version of Virtualbox](#virtualbox).
 
+### Docker and AVX2 Support
+
+By default, the Pony Docker image is compiled without support for AVX CPU instructions. For optimal performance, you should build your Pony installation from source.
 
 ## Linux using an RPM package (via Bintray)
 
@@ -79,6 +82,10 @@ Or, for master builds:
 yum install ponyc-master
 ```
 
+### RPM and AVX2 Support
+
+By default, the Pony RPM package is compiled without support for AVX CPU instructions. For optimal performance, you should build your Pony installation from source.
+
 ## Linux using a DEB package (via Bintray)
 
 For Ubuntu or Debian Linux, the `master` and `release` branches are packaged and available on Bintray ([pony-language/ponyc-debian](https://bintray.com/pony-language/ponyc-debian)).
@@ -97,6 +104,10 @@ Or, for master builds:
 sudo apt-get install ponyc-master
 ```
 
+### DEB and AVX2 Support
+
+By default, the Pony DEB package is compiled without support for AVX CPU instructions. For optimal performance, you should build your Pony installation from source.
+
 ## Arch Linux
 
 ```bash
@@ -382,9 +393,8 @@ Pony binaries can trigger illegal instruction errors under VirtualBox 4.x, for a
 
 Use VirtualBox 5.x to avoid possible problems.
 
-## AVX2 Support
 
-The Pony prebuilt binaries trigger illegal instruction errors under CPUs without [AVX2](https://en.wikipedia.org/wiki/Advanced_Vector_Extensions#Advanced_Vector_Extensions_2) support.
+You can learn more about [AVX2](https://en.wikipedia.org/wiki/Advanced_Vector_Extensions#Advanced_Vector_Extensions_2) support.
 
 ## Building Pony on Non-x86 platforms