Case 112: LP64 → ILP64 integer-model switch (oneMKL MKL_INT 32→64)¶

Field	Value
Verdict	🔴 BREAKING
Category	Breaking
Platforms	Linux
Flags	ABI break
Detected `ChangeKind`s	`integer_model_changed`
Source files	`examples/case112_lp64_ilp64/`

Category: Binary ABI break / numerical-library ABI hazard | Verdict: 🔴 BREAKING

What changed¶

v1 is the LP64 interface: MKL_INT is int (32-bit). v2 is the ILP64 interface: MKL_INT is long (64-bit). Every public entry point that takes a dimension, stride, or count — and the functions that return one — flips its integer width at the same time. The function names are unchanged (they are extern "C"), so a consumer linked against the LP64 build resolves the ILP64 symbols at load time but passes/reads integers with the wrong width: array indices and lengths are silently truncated or sign-extended.

This is the highest-value numerical-library ABI hazard: for example oneMKL ships both interfaces and they are not interchangeable.

How abicheck catches it¶

integer_model_changed fires because a large fraction of public integer parameters/returns flip width together and the MKL_INT integer typedef changes its underlying size (int → long), which is the signature of an LP64↔ILP64 switch. Individual func_params_changed / func_return_changed findings are still reported per symbol; the grouped diagnostic names the root cause.

Files¶

v1.h / v2.h — the LP64 and ILP64 header versions
v1.c / v2.c — the two library builds
app.c — consumer built against the LP64 interface

Source files¶

CMakeLists.txt
app.c
v1.c
v1.h
v2.c
v2.h