V0.3 dev

.devcontainer/Dockerfile

@@ -1,5 +1,6 @@
 # FROM mcr.microsoft.com/devcontainers/cpp:1-ubuntu-24.04
-FROM mcr.microsoft.com/devcontainers/go:1-1.24-bookworm
+# FROM mcr.microsoft.com/devcontainers/go
+FROM golang:tip-trixie
 
 # ARG REINSTALL_CMAKE_VERSION_FROM_SOURCE="none"
 
@@ -11,7 +12,7 @@ FROM mcr.microsoft.com/devcontainers/go:1-1.24-bookworm
 # [Optional] Uncomment this section to install additional packages.
 # RUN apt-get update && export DEBIAN_FRONTEND=noninteractive \
 #     && apt-get -y install --no-install-recommends <your-package-list-here>
-RUN apt update && apt -y upgrade && export DEBIAN_FRONTEND=noninteractive && apt -y install openmpi-bin openmpi-doc libopenmpi-dev
+RUN apt update && apt -y upgrade && export DEBIAN_FRONTEND=noninteractive && apt -y install openmpi-bin openmpi-doc libopenmpi-dev jq
 
 WORKDIR /tmp
 RUN wget https://mvapich.cse.ohio-state.edu/download/mvapich/osu-micro-benchmarks-7.5.1.tar.gz
@@ -20,6 +21,12 @@ WORKDIR /tmp/osu-micro-benchmarks-7.5.1
 RUN ./configure CC=/usr/bin/mpicc CXX=/usr/bin/mpicxx
 RUN make && make install
 RUN go install golang.org/x/tools/cmd/stringer@latest
+RUN go install github.com/go-delve/delve/cmd/dlv@latest
+
+RUN useradd -m -s /bin/bash vscode
+ENV GOPATH=/home/vscode/go
+ENV PATH=$PATH:/home/vscode/go/bin
+USER vscode
 
 
 # RUN update-alternatives --install /usr/bin/clangd clangd /usr/bin/clangd-19 100

.devcontainer/devcontainer.json

@@ -4,22 +4,14 @@
 	"name": "Go",
 	"build": {
 		"dockerfile": "Dockerfile"
+	},
+	"remoteUser": "vscode",
+	"customizations": {
+		"vscode": {
+			"extensions": [
+				"golang.go",
+				"anthropic.claude-code"
+			]
+		}
 	}
-	// Or use a Dockerfile or Docker Compose file. More info: https://containers.dev/guide/dockerfile
-	// "image": "mcr.microsoft.com/devcontainers/go:1-1.24-bookworm"
-
-	// Features to add to the dev container. More info: https://containers.dev/features.
-	// "features": {},
-
-	// Use 'forwardPorts' to make a list of ports inside the container available locally.
-	// "forwardPorts": [],
-
-	// Use 'postCreateCommand' to run commands after the container is created.
-	// "postCreateCommand": "go version",
-
-	// Configure tool-specific properties.
-	// "customizations": {},
-
-	// Uncomment to connect as root instead. More info: https://aka.ms/dev-containers-non-root.
-	// "remoteUser": "root"
 }

.github/workflows/ci.yml

@@ -1,25 +1,29 @@
 on: [push, pull_request]
 name: Test
+
 jobs:
   test:
-    strategy:
-      matrix:
-        go-version: [1.24.x]
-        os: [ubuntu-latest]
-    runs-on: ${{ matrix.os }}
+    runs-on: ubuntu-latest
     steps:
-    - name: Install Go
-      uses: actions/setup-go@v2
+    - name: Checkout code
+      uses: actions/checkout@v4
+
+    - name: Install Stable Go for Bootstrap
+      uses: actions/setup-go@v6
       with:
-        go-version: ${{ matrix.go-version }}
+        go-version: 'stable'
+
+    - name: Download Go Tip
+      run: |
+        go install golang.org/dl/gotip@latest
+        gotip download
+        echo "$HOME/sdk/gotip/bin" >> $GITHUB_PATH
+
     - name: Install OpenMPI
-      if: matrix.os == 'ubuntu-latest'
-      run: sudo apt update && sudo apt install -y --no-install-recommends libopenmpi-dev openmpi-common openmpi-bin
-    - name: Checkout code
-      uses: actions/checkout@v2
-    - name: Install Stringer
-      run: go install golang.org/x/tools/cmd/stringer@latest
-    - name: Build and Install
-      run: make install
+      run: sudo apt update && sudo apt install -y --no-install-recommends openmpi-bin libopenmpi-dev
+
+    - name: Build
+      run: go build ./...
+
     - name: Test
-      run: make test
+      run: mpirun -n 4 --oversubscribe go test .

.gitignore

@@ -1,3 +1,3 @@
 xautogencgoflags.go
 oldtests/
-cmd/latency
+cmd/latency/latency

LICENSE.md

@@ -1,4 +1,4 @@
-Copyright (c) 2021, Seth Bromberger All rights reserved.
+Copyright (c) 2026, Seth Bromberger All rights reserved.
 
 Please note the following limitation with respect to redistribution:
 
@@ -13,3 +13,8 @@ Redistribution and use in source and binary forms without modification, and use
 1. Neither the name of the copyright holder nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.
 
 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+
+## Note on the No-Modification Redistribution Clause
+The prohibition on redistribution of modified source code is intentional and specific. It is not intended to prevent private modification or internal use: you are free to modify this software for your own purposes. Rather, it is intended to prevent automated or pipeline-driven modification of this source code prior to or during redistribution, such as the insertion of telemetry, tracking, or analytics code by a package registry, build system, or other distribution intermediary, as well as the distribution of modified copies containing malicious code. Any copy of this software that is redistributed must be identical to what was published by the copyright holder.
+

MIGRATION.md

@@ -0,0 +1,210 @@
+# Migration Guide
+
+## Migrating from v0.2 to v0.3
+
+### Initialization and teardown
+
+The package-level `Start`, `Stop`, `WorldRank`, `WorldSize`, and `WorldTime`
+functions have been replaced by a session object.
+
+```go
+// v0.2
+mpi.Start(false)
+defer mpi.Stop()
+rank := mpi.WorldRank()
+size := mpi.WorldSize()
+```
+
+```go
+// v0.3
+m, err := mpi.Start()
+if err != nil {
+    log.Fatal(err)
+}
+defer m.Stop()
+rank := m.WorldRank()
+size := m.WorldSize()
+```
+
+For threaded initialization:
+
+```go
+// v0.2
+mpi.Start(true)
+
+// v0.3
+m, err := mpi.StartThreaded()
+```
+
+### Initialization check
+
+```go
+// v0.2
+mpi.IsOn()
+
+// v0.3
+mpi.IsInitialized()
+```
+
+### Communicators
+
+`NewCommunicator` is now a method on `*MPI` rather than a package-level function.
+
+```go
+// v0.2
+comm := mpi.NewCommunicator(nil)
+
+// v0.3
+comm := m.NewCommunicator(nil)
+```
+
+### Send and receive
+
+All type-specific send/receive methods (`SendBytes`, `SendInt32s`, `SendFloat64s`,
+etc.) have been replaced by generic methods.
+
+```go
+// v0.2
+comm.SendFloat64s(vals, toID, tag)
+vals, status := comm.RecvFloat64s(fromID, tag)
+comm.RecvPreallocFloat64s(vals, fromID, tag)
+```
+
+```go
+// v0.3
+comm.Send(vals, toID, tag)
+vals, status := comm.Recv[float64](fromID, tag)
+comm.RecvPrealloc(vals, fromID, tag)
+```
+
+The same pattern applies to all types: `byte`, `int8`, `int16`, `uint16`,
+`int32`, `uint32`, `int64`, `uint64`, `float32`, `float64`, `complex64`,
+`complex128`.
+
+### Single-value send/receive
+
+```go
+// v0.2
+comm.SendFloat64(v, toID, tag)
+v, status := comm.RecvFloat64(fromID, tag)
+```
+
+```go
+// v0.3
+comm.SendOne(v, toID, tag)
+v, status := comm.RecvOne[float64](fromID, tag)
+```
+
+### Broadcast
+
+```go
+// v0.2
+comm.BcastFloat64s(vals, root)
+
+// v0.3
+comm.Bcast(vals, root)
+```
+
+### Reduce and Allreduce
+
+```go
+// v0.2
+comm.ReduceFloat64s(dest, orig, mpi.OpSum, root)
+comm.AllreduceFloat64s(dest, orig, mpi.OpSum, root)
+
+// v0.3
+comm.Reduce(dest, orig, mpi.OpSum, root)
+comm.Allreduce(dest, orig, mpi.OpSum)
+```
+
+Note that `Allreduce` no longer takes a `root` parameter. The v0.2 parameter
+was accepted but never used; v0.3 removes it.
+
+### Status
+
+`Status` is now a value type. Methods that previously returned `*Status` now
+return `Status`.
+
+`Count` (formerly `GetCount`) is now generic and no longer takes a `DataType` argument, and has
+been renamed along with other `Status` methods.
+
+| v0.2 | v0.3 |
+|------|------|
+| `Status.GetSource()` | `Status.Source()` |
+| `Status.GetTag()` | `Status.Tag()` |
+| `Status.GetError()` | `Status.Error()` |
+| `Status.GetCount(mpi.Byte)` | `Status.Count[byte]()` |
+
+### Mprobe and Mrecv
+
+The v0.2 API exposed `C.MPI_Message` directly. In v0.3 this is encapsulated
+in `MatchedMessage`.
+
+```go
+// v0.2
+status, msg := comm.Mprobe(fromID, tag)
+n := status.GetCount(mpi.Byte)
+buf := make([]byte, n)
+comm.MrecvPreallocBytes(buf, fromID, tag, msg)
+```
+
+```go
+// v0.3
+m := comm.Mprobe(fromID, tag)
+buf, status := m.Recv[byte]()
+// or, with a preallocated buffer:
+status = m.RecvPrealloc(buf)
+```
+
+`Mrecv` is also available as a single call:
+
+```go
+buf, status := comm.Mrecv[byte](fromID, tag)
+```
+
+`MatchedMessage` methods follow the same naming convention as `Status`:
+
+| v0.2 | v0.3 |
+|------|------|
+| `MatchedMessage.GetSource()` | `MatchedMessage.Source()` |
+| `MatchedMessage.GetTag()` | `MatchedMessage.Tag()` |
+| `MatchedMessage.GetError()` | `MatchedMessage.Error()` |
+| `MatchedMessage.GetCount[T]()` | `MatchedMessage.Count[T]()` |
+
+### Communicator methods
+
+| v0.2 | v0.3 |
+|------|------|
+| `Communicator.GetAttr()` | `Communicator.Attr()` |
+| `Communicator.GetMaxTag()` | `Communicator.MaxTag()` |
+
+### Communicator.MaxTag field removed
+
+The exported `MaxTag` field on `Communicator` has been unexported. Use
+`Communicator.MaxTag()` if you need this value.
+
+### DataType removed
+
+The exported `DataType` constants (`mpi.Byte`, `mpi.Int`, `mpi.Float`,
+`mpi.Double`, etc.) have been removed. Type information is now conveyed through
+Go generics and is not part of the public API.
+
+### Iprobe
+
+`Iprobe` now returns a value `Status` rather than a pointer.
+
+### String convenience methods
+
+`SendString` and `RecvString` have been removed. Use `Send` and `Recv` with a
+`[]byte` conversion:
+
+```go
+// v0.2
+comm.SendString(s, toID, tag)
+s, status := comm.RecvString(fromID, tag)
+
+// v0.3
+comm.Send([]byte(s), toID, tag)
+b, status := comm.Recv[byte](fromID, tag)
+s := string(b)
+```