1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
//! Integration test for `CustomDatatype::contiguous`.
//!
//! Exercises:
//! - Successful construction and `raw_handle() >= 0`
//! - Count=0 returns an MPI error (`Count` or `Arg` class, implementation-defined)
//! - Indexed-basetype rejection returns `Error::InvalidOp` before any FFI call
//! - Drop frees the underlying MPI handle (no double-free on exit)
//!
//! All assertions are protected by a sentinel allreduce(Min) before any
//! `process::exit` call so that no rank exits while others are still inside MPI.
//!
//! Run with: mpiexec -n 2 ./target/debug/examples/test_custom_dt_contiguous
use ferrompi::{CustomDatatype, DatatypeTag, Error, Mpi, MpiErrorClass, ReduceOp};
fn main() {
let mpi = Mpi::init().expect("MPI init failed");
let world = mpi.world();
let rank = world.rank();
// local_ok tracks whether this rank passed all its assertions.
let mut local_ok = true;
// ========================================================================
// Test 1: contiguous(10, F64) returns Ok with raw_handle() >= 0
// ========================================================================
{
match CustomDatatype::contiguous(10, DatatypeTag::F64) {
Ok(dt) => {
let h = dt.raw_handle();
if h >= 0 {
if rank == 0 {
println!("PASS: Test 1 — contiguous(10, F64) raw_handle = {h}");
}
} else {
eprintln!("rank {rank}: FAIL Test 1 — raw_handle = {h}, expected >= 0");
local_ok = false;
}
// dt drops here, freeing the MPI handle
}
Err(e) => {
eprintln!("rank {rank}: FAIL Test 1 — contiguous(10, F64) returned Err: {e}");
local_ok = false;
}
}
}
// ========================================================================
// Test 2: contiguous(0, F64) returns an MPI error.
//
// MPI_Type_contiguous with count=0 returns MPI_ERR_COUNT on most
// implementations, but MPI_ERR_ARG on some (e.g., MPICH 4.x). Both are
// acceptable per the MPI standard (the standard says count must be >= 0,
// but error reporting is implementation-defined).
// ========================================================================
{
match CustomDatatype::contiguous(0, DatatypeTag::F64) {
Err(Error::Mpi { class, .. }) => {
let accepted = matches!(class, MpiErrorClass::Count | MpiErrorClass::Arg);
if accepted {
if rank == 0 {
println!("PASS: Test 2 — contiguous(0, F64) returned Err({class:?}) (implementation-defined Count or Arg)");
}
} else {
eprintln!("rank {rank}: FAIL Test 2 — contiguous(0, F64) returned unexpected class {class:?}");
local_ok = false;
}
}
Err(e) => {
eprintln!(
"rank {rank}: FAIL Test 2 — contiguous(0, F64) returned unexpected error: {e}"
);
local_ok = false;
}
Ok(dt) => {
// Some MPI implementations (notably Open MPI >= 5.0) accept
// count=0 and produce a valid zero-size datatype. This is
// technically conforming; accept it but emit a note.
if rank == 0 {
println!(
"NOTE: Test 2 — contiguous(0, F64) succeeded (raw_handle={}) — \
MPI implementation accepts count=0 (conforming)",
dt.raw_handle()
);
}
}
}
}
// ========================================================================
// Test 3: contiguous(5, FloatInt) returns Err(Error::InvalidOp) without
// calling into MPI (pre-FFI validation in the Rust wrapper)
// ========================================================================
{
match CustomDatatype::contiguous(5, DatatypeTag::FloatInt) {
Err(Error::InvalidOp) => {
if rank == 0 {
println!("PASS: Test 3 — contiguous(5, FloatInt) returned Err(InvalidOp)");
}
}
other => {
eprintln!(
"rank {rank}: FAIL Test 3 — expected Err(InvalidOp), got: {:?}",
other.err()
);
local_ok = false;
}
}
}
// ========================================================================
// Test 4: Multiple CustomDatatype instances all drop cleanly
// ========================================================================
{
let mut success = true;
let tags = [
DatatypeTag::F32,
DatatypeTag::F64,
DatatypeTag::I32,
DatatypeTag::I64,
DatatypeTag::U8,
DatatypeTag::U32,
DatatypeTag::U64,
DatatypeTag::Byte,
];
for tag in tags {
match CustomDatatype::contiguous(4, tag) {
Ok(dt) => {
if dt.raw_handle() < 0 {
eprintln!("rank {rank}: FAIL Test 4 — contiguous(4, {tag:?}) handle < 0");
success = false;
}
// Drop frees the handle
}
Err(e) => {
eprintln!("rank {rank}: FAIL Test 4 — contiguous(4, {tag:?}) failed: {e}");
success = false;
}
}
}
if success {
if rank == 0 {
println!("PASS: Test 4 — all primitive base types construct and drop cleanly");
}
} else {
local_ok = false;
}
}
// ========================================================================
// Sentinel allreduce: every rank must reach this point.
// Reduces local_ok across all ranks so that any per-rank failure causes
// the whole job to exit non-zero.
// ========================================================================
let local_flag: i32 = if local_ok { 1 } else { 0 };
let global_flag = match world.allreduce_scalar(local_flag, ReduceOp::Min) {
Ok(v) => v,
Err(e) => {
eprintln!("rank {rank}: sentinel allreduce failed: {e}");
std::process::exit(1);
}
};
if global_flag == 0 {
if rank == 0 {
eprintln!("FAIL: one or more ranks reported a test failure");
}
std::process::exit(1);
}
if rank == 0 {
println!("\n========================================");
println!("All custom datatype contiguous tests passed!");
println!("========================================");
}
}