Stream: git-wasmtime

Topic: wasmtime / issue #14131 Debug assert in alias analysis pass

Wasmtime GitHub notifications bot (Aug 13 2026 at 00:23):

alexcrichton opened issue #14131:

This input:

test compile
set opt_level=speed_and_size
target x86_64

function %f(i64, i64) system_v {
    region0 = 1 "table"

block0(v0: i64, v1: i64):
    v2 = iconst.i32 0
    store notrap v2, v1
    store notrap region0 v2, v0
    store notrap region0 v2, v0
    fence
    return
}

yields:

$ cargo run -p cranelift-tools -- test alias-analysis-observed-stores.clif

    Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.08s
     Running `target/debug/clif-util test alias-analysis-observed-stores.clif`

thread 'worker #3' (3228052) panicked at cranelift/codegen/src/alias_analysis.rs:971:9:
assertion `left == right` failed: `compute_block_input_states` should have already found all observed stores, but processing inst3 found a new one
  left: 2
 right: 3
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
[2026-08-13T00:22:26Z ERROR cranelift_filetests::concurrent] FAIL: panicked in worker #3: assertion `left == right` failed: `compute_block_input_states` should have already found all observed stores, but processing inst3 found a new one
      left: 2
     right: 3
FAIL alias-analysis-observed-stores.clif: panicked in worker #3: assertion `left == right` failed: `compute_block_input_states` should have already found all observed stores, but processing inst3 found a new one
  left: 2
 right: 3
1 tests
Error: 1 failure

The original fuzz input for this is input.txt

cc @fitzgen

Wasmtime GitHub notifications bot (Aug 13 2026 at 00:23):

alexcrichton added the fuzz-bug label to Issue #14131.

Wasmtime GitHub notifications bot (Aug 13 2026 at 16:19):

fitzgen assigned fitzgen to issue #14131.

Wasmtime GitHub notifications bot (Aug 13 2026 at 23:36):

fitzgen closed issue #14131:

This input:

test compile
set opt_level=speed_and_size
target x86_64

function %f(i64, i64) system_v {
    region0 = 1 "table"

block0(v0: i64, v1: i64):
    v2 = iconst.i32 0
    store notrap v2, v1
    store notrap region0 v2, v0
    store notrap region0 v2, v0
    fence
    return
}

yields:

$ cargo run -p cranelift-tools -- test alias-analysis-observed-stores.clif

    Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.08s
     Running `target/debug/clif-util test alias-analysis-observed-stores.clif`

thread 'worker #3' (3228052) panicked at cranelift/codegen/src/alias_analysis.rs:971:9:
assertion `left == right` failed: `compute_block_input_states` should have already found all observed stores, but processing inst3 found a new one
  left: 2
 right: 3
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
[2026-08-13T00:22:26Z ERROR cranelift_filetests::concurrent] FAIL: panicked in worker #3: assertion `left == right` failed: `compute_block_input_states` should have already found all observed stores, but processing inst3 found a new one
      left: 2
     right: 3
FAIL alias-analysis-observed-stores.clif: panicked in worker #3: assertion `left == right` failed: `compute_block_input_states` should have already found all observed stores, but processing inst3 found a new one
  left: 2
 right: 3
1 tests
Error: 1 failure

The original fuzz input for this is input.txt

cc @fitzgen

Last updated: Aug 30 2026 at 09:07 UTC