all: replace dep with Go modules

We've moved to go modules, and keeping both working is burdensome.
In fact, I think dep already wasn't working.

Author: aykevl

.circleci/config.yml

@@ -61,18 +61,19 @@ commands:
       - install-node
       - restore_cache:
           keys:
-            - go-cache-{{ checksum "Gopkg.lock" }}-{{ .Environment.CIRCLE_PREVIOUS_BUILD_NUM }}
-            - go-cache-{{ checksum "Gopkg.lock" }}
+            - go-cache-v2-{{ checksum "go.mod" }}-{{ .Environment.CIRCLE_PREVIOUS_BUILD_NUM }}
+            - go-cache-v2-{{ checksum "go.mod" }}
       - llvm-source-linux
       - run: go install .
       - run: go test -v
       - run: make gen-device -j4
       - run: make smoketest RISCV=0
       - save_cache:
-          key: go-cache-{{ checksum "Gopkg.lock" }}-{{ .Environment.CIRCLE_BUILD_NUM }}
+          key: go-cache-v2-{{ checksum "go.mod" }}-{{ .Environment.CIRCLE_BUILD_NUM }}
           paths:
             - ~/.cache/go-build
             - ~/.cache/tinygo
+            - /go/pkg/mod
       - run: make fmt-check
   build-linux:
     steps:
@@ -95,8 +96,8 @@ commands:
       - install-node
       - restore_cache:
           keys:
-            - go-cache-{{ checksum "Gopkg.lock" }}-{{ .Environment.CIRCLE_PREVIOUS_BUILD_NUM }}
-            - go-cache-{{ checksum "Gopkg.lock" }}
+            - go-cache-v2-{{ checksum "go.mod" }}-{{ .Environment.CIRCLE_PREVIOUS_BUILD_NUM }}
+            - go-cache-v2-{{ checksum "go.mod" }}
       - llvm-source-linux
       - restore_cache:
           keys:
@@ -138,10 +139,11 @@ commands:
       - store_artifacts:
           path: /tmp/tinygo.linux-amd64.tar.gz
       - save_cache:
-          key: go-cache-{{ checksum "Gopkg.lock" }}-{{ .Environment.CIRCLE_BUILD_NUM }}
+          key: go-cache-v2-{{ checksum "go.mod" }}-{{ .Environment.CIRCLE_BUILD_NUM }}
           paths:
             - ~/.cache/go-build
             - ~/.cache/tinygo
+            - /go/pkg/mod
       - run:
           name: "Extract release tarball"
           command: |

BUILDING.md

@@ -16,7 +16,6 @@ LLVM, Clang and LLD are quite light on dependencies, requiring only standard
 build tools to be built. Go is of course necessary to build TinyGo itself.
 
   * Go (1.11+)
-  * [dep](https://golang.github.io/dep/)
   * Standard build tools (gcc/clang)
   * git
   * CMake
@@ -28,15 +27,19 @@ on a different system like Mac.
 ## Download the source
 
 The first step is to download the TinyGo sources (use `--recursive` if you clone
-the git repository). Then, inside the directory, perform these steps:
+the git repository). Then, inside the directory, download the LLVM source:
 
-    dep ensure -vendor-only # download Go dependencies
-    make llvm-source        # download LLVM
+    make llvm-source
 
 You can also store LLVM outside of the TinyGo root directory by setting the
 `LLVM_BUILDDIR`, `CLANG_SRC` and `LLD_SRC` make variables, but that is not
 covered by this guide.
 
+TinyGo uses Go modules, so if you clone TinyGo inside your GOPATH (and are using
+Go below 1.13), make sure that Go modules are enabled:
+
+    export GO111MODULE=on
+
 ## Build LLVM, Clang, LLD
 
 Before starting the build, you may want to set the following environment

Dockerfile

@@ -6,26 +6,23 @@ RUN wget -O- https://apt.llvm.org/llvm-snapshot.gpg.key| apt-key add - && \
     apt-get update && \
     apt-get install -y llvm-8-dev libclang-8-dev git
 
-RUN wget -O- https://raw.githubusercontent.com/golang/dep/master/install.sh | sh
-
-COPY . /go/src/github.com/tinygo-org/tinygo
+COPY . /tinygo
 
 # remove submodules directories and re-init them to fix any hard-coded paths
 # after copying the tinygo directory in the previous step.
-RUN cd /go/src/github.com/tinygo-org/tinygo/ && \
+RUN cd /tinygo/ && \
     rm -rf ./lib/* && \
     git submodule update --init --recursive --force
 
-RUN cd /go/src/github.com/tinygo-org/tinygo/ && \
-    dep ensure --vendor-only && \
-    go install /go/src/github.com/tinygo-org/tinygo/
+RUN cd /tinygo/ && \
+    go install /tinygo/
 
 # tinygo-wasm stage installs the needed dependencies to compile TinyGo programs for WASM.
 FROM tinygo-base AS tinygo-wasm
 
 COPY --from=tinygo-base /go/bin/tinygo /go/bin/tinygo
-COPY --from=tinygo-base /go/src/github.com/tinygo-org/tinygo/src /go/src/github.com/tinygo-org/tinygo/src
-COPY --from=tinygo-base /go/src/github.com/tinygo-org/tinygo/targets /go/src/github.com/tinygo-org/tinygo/targets
+COPY --from=tinygo-base /tinygo/src /tinygo/src
+COPY --from=tinygo-base /tinygo/targets /tinygo/targets
 
 RUN wget -O- https://apt.llvm.org/llvm-snapshot.gpg.key| apt-key add - && \
     echo "deb http://apt.llvm.org/buster/ llvm-toolchain-buster-8 main" >> /etc/apt/sources.list && \
@@ -36,13 +33,13 @@ RUN wget -O- https://apt.llvm.org/llvm-snapshot.gpg.key| apt-key add - && \
 FROM tinygo-base AS tinygo-avr
 
 COPY --from=tinygo-base /go/bin/tinygo /go/bin/tinygo
-COPY --from=tinygo-base /go/src/github.com/tinygo-org/tinygo/src /go/src/github.com/tinygo-org/tinygo/src
-COPY --from=tinygo-base /go/src/github.com/tinygo-org/tinygo/targets /go/src/github.com/tinygo-org/tinygo/targets
-COPY --from=tinygo-base /go/src/github.com/tinygo-org/tinygo/Makefile /go/src/github.com/tinygo-org/tinygo/
-COPY --from=tinygo-base /go/src/github.com/tinygo-org/tinygo/tools /go/src/github.com/tinygo-org/tinygo/tools
-COPY --from=tinygo-base /go/src/github.com/tinygo-org/tinygo/lib /go/src/github.com/tinygo-org/tinygo/lib
+COPY --from=tinygo-base /tinygo/src /tinygo/src
+COPY --from=tinygo-base /tinygo/targets /tinygo/targets
+COPY --from=tinygo-base /tinygo/Makefile /tinygo/
+COPY --from=tinygo-base /tinygo/tools /tinygo/tools
+COPY --from=tinygo-base /tinygo/lib /tinygo/lib
 
-RUN cd /go/src/github.com/tinygo-org/tinygo/ && \
+RUN cd /tinygo/ && \
     apt-get update && \
     apt-get install -y apt-utils python3 make binutils-avr gcc-avr avr-libc && \
     make gen-device-avr && \
@@ -54,13 +51,13 @@ RUN cd /go/src/github.com/tinygo-org/tinygo/ && \
 FROM tinygo-base AS tinygo-arm
 
 COPY --from=tinygo-base /go/bin/tinygo /go/bin/tinygo
-COPY --from=tinygo-base /go/src/github.com/tinygo-org/tinygo/src /go/src/github.com/tinygo-org/tinygo/src
-COPY --from=tinygo-base /go/src/github.com/tinygo-org/tinygo/targets /go/src/github.com/tinygo-org/tinygo/targets
-COPY --from=tinygo-base /go/src/github.com/tinygo-org/tinygo/Makefile /go/src/github.com/tinygo-org/tinygo/
-COPY --from=tinygo-base /go/src/github.com/tinygo-org/tinygo/tools /go/src/github.com/tinygo-org/tinygo/tools
-COPY --from=tinygo-base /go/src/github.com/tinygo-org/tinygo/lib /go/src/github.com/tinygo-org/tinygo/lib
+COPY --from=tinygo-base /tinygo/src /tinygo/src
+COPY --from=tinygo-base /tinygo/targets /tinygo/targets
+COPY --from=tinygo-base /tinygo/Makefile /tinygo/
+COPY --from=tinygo-base /tinygo/tools /tinygo/tools
+COPY --from=tinygo-base /tinygo/lib /tinygo/lib
 
-RUN cd /go/src/github.com/tinygo-org/tinygo/ && \
+RUN cd /tinygo/ && \
     apt-get update && \
     apt-get install -y apt-utils python3 make clang-8 && \
     make gen-device-nrf && make gen-device-stm32 && \
@@ -71,11 +68,11 @@ RUN cd /go/src/github.com/tinygo-org/tinygo/ && \
 # tinygo-all stage installs the needed dependencies to compile TinyGo programs for all platforms.
 FROM tinygo-wasm AS tinygo-all
 
-COPY --from=tinygo-base /go/src/github.com/tinygo-org/tinygo/Makefile /go/src/github.com/tinygo-org/tinygo/
-COPY --from=tinygo-base /go/src/github.com/tinygo-org/tinygo/tools /go/src/github.com/tinygo-org/tinygo/tools
-COPY --from=tinygo-base /go/src/github.com/tinygo-org/tinygo/lib /go/src/github.com/tinygo-org/tinygo/lib
+COPY --from=tinygo-base /tinygo/Makefile /tinygo/
+COPY --from=tinygo-base /tinygo/tools /tinygo/tools
+COPY --from=tinygo-base /tinygo/lib /tinygo/lib
 
-RUN cd /go/src/github.com/tinygo-org/tinygo/ && \
+RUN cd /tinygo/ && \
     apt-get update && \
     apt-get install -y apt-utils python3 make clang-8 binutils-avr gcc-avr avr-libc && \
     make gen-device && \