QP segfaulting on 32bits linux

[joaquimg]

The following file trigger the fail

sampled_quadratic_32bit.mps.txt

I found it working on LinearDecisionRules.jl and trackd the issue here: bfpc/LinearDecisionRules.jl#35
In this PR I am loading the file and running it.

here is the stack trace:

Running HiGHS 1.13.1 (git hash: 1d267d97c): Copyright (c) 2026 under Apache 2.0 license terms
Using BLAS: blastrampoline 
QP has 400 rows; 8 cols; 1100 matrix nonzeros; 10 Hessian nonzeros
Coefficient ranges:
  Matrix  [1e-03, 1e+00]
  Cost    [1e-01, 1e+00]
  Hessian [1e-02, 2e+00]
  Bound   [0e+00, 0e+00]
  RHS     [1e-03, 1e+00]
  Iteration        Objective     NullspaceDim
terminate called after throwing an instance of 'std::bad_alloc'
  what():  std::bad_alloc
[3306] signal (6.-6): Aborted
in expression starting at /home/runner/work/LinearDecisionRules.jl/LinearDecisionRules.jl/test/runtests.jl:2803
__kernel_vsyscall at linux-gate.so.1 (unknown line)
unknown function (ip: 0xf6095016)
gsignal at /lib32/libc.so.6 (unknown line)
abort at /lib32/libc.so.6 (unknown line)
unknown function (ip: 0xf5da1f70)
unknown function (ip: 0xf5dbba96)
_ZSt9terminatev at /lib32/libstdc++.so.6 (unknown line)
__cxa_throw at /lib32/libstdc++.so.6 (unknown line)
unknown function (ip: 0xf5da1972)
_ZNSt6vectorISt4pairIN8presolve19HighsPostsolveStack13ReductionTypeEjESaIS4_EE19_M_emplace_back_auxIJRS3_RjEEEvDpOT_ at /home/runner/.julia/artifacts/599bbfbf9ca7f67a75c299331047cc51d7f06acf/lib/libhighs.so (unknown line)
_ZNSt6vectorISt4pairIN8presolve19HighsPostsolveStack13ReductionTypeEjESaIS4_EE12emplace_backIJRS3_RjEEEvDpOT_ at /home/runner/.julia/artifacts/599bbfbf9ca7f67a75c299331047cc51d7f06acf/lib/libhighs.so (unknown line)
_ZN8presolve19HighsPostsolveStack12redundantRowEi at /home/runner/.julia/artifacts/599bbfbf9ca7f67a75c299331047cc51d7f06acf/lib/libhighs.so (unknown line)
_ZN8presolve9HPresolve11rowPresolveERNS_19HighsPostsolveStackEi at /home/runner/.julia/artifacts/599bbfbf9ca7f67a75c299331047cc51d7f06acf/lib/libhighs.so (unknown line)
_ZN8presolve9HPresolve24removeDoubletonEquationsERNS_19HighsPostsolveStackE at /home/runner/.julia/artifacts/599bbfbf9ca7f67a75c299331047cc51d7f06acf/lib/libhighs.so (unknown line)
_ZN8presolve9HPresolve16fastPresolveLoopERNS_19HighsPostsolveStackE at /home/runner/.julia/artifacts/599bbfbf9ca7f67a75c299331047cc51d7f06acf/lib/libhighs.so (unknown line)
_ZN8presolve9HPresolve8presolveERNS_19HighsPostsolveStackE at /home/runner/.julia/artifacts/599bbfbf9ca7f67a75c299331047cc51d7f06acf/lib/libhighs.so (unknown line)
_ZN8presolve9HPresolve3runERNS_19HighsPostsolveStackE at /home/runner/.julia/artifacts/599bbfbf9ca7f67a75c299331047cc51d7f06acf/lib/libhighs.so (unknown line)
_ZN17PresolveComponent3runEv at /home/runner/.julia/artifacts/599bbfbf9ca7f67a75c299331047cc51d7f06acf/lib/libhighs.so (unknown line)
_ZN5Highs11runPresolveEbb at /home/runner/.julia/artifacts/599bbfbf9ca7f67a75c299331047cc51d7f06acf/lib/libhighs.so (unknown line)
_ZN5Highs19calledOptimizeModelEv at /home/runner/.julia/artifacts/599bbfbf9ca7f67a75c299331047cc51d7f06acf/lib/libhighs.so (unknown line)
_ZN5Highs13optimizeModelEv at /home/runner/.julia/artifacts/599bbfbf9ca7f67a75c299331047cc51d7f06acf/lib/libhighs.so (unknown line)
_ZN5Highs13optimizeHighsEv at /home/runner/.julia/artifacts/599bbfbf9ca7f67a75c299331047cc51d7f06acf/lib/libhighs.so (unknown line)
_ZN5Highs3runEv at /home/runner/.julia/artifacts/599bbfbf9ca7f67a75c299331047cc51d7f06acf/lib/libhighs.so (unknown line)
_ZL25computeStartingPointHighsR8InstanceR8SettingsR10StatisticsR13QpModelStatusR21QpHotstartInformationR16HighsModelStatusR10HighsBasisR13HighsSolutionR10HighsTimer.isra.327 at /home/runner/.julia/artifacts/599bbfbf9ca7f67a75c299331047cc51d7f06acf/lib/libhighs.so (unknown line)
_Z7solveqpR8InstanceR8SettingsR10StatisticsR16HighsModelStatusR10HighsBasisR13HighsSolutionR10HighsTimer at /home/runner/.julia/artifacts/599bbfbf9ca7f67a75c299331047cc51d7f06acf/lib/libhighs.so (unknown line)
_ZN5Highs11callSolveQpEv at /home/runner/.julia/artifacts/599bbfbf9ca7f67a75c299331047cc51d7f06acf/lib/libhighs.so (unknown line)
_ZN5Highs19calledOptimizeModelEv at /home/runner/.julia/artifacts/599bbfbf9ca7f67a75c299331047cc51d7f06acf/lib/libhighs.so (unknown line)
_ZN5Highs13optimizeModelEv at /home/runner/.julia/artifacts/599bbfbf9ca7f67a75c299331047cc51d7f06acf/lib/libhighs.so (unknown line)
_ZN5Highs13optimizeHighsEv at /home/runner/.julia/artifacts/599bbfbf9ca7f67a75c299331047cc51d7f06acf/lib/libhighs.so (unknown line)
_ZN5Highs3runEv at /home/runner/.julia/artifacts/599bbfbf9ca7f67a75c299331047cc51d7f06acf/lib/libhighs.so (unknown line)
Highs_run at /home/runner/.julia/artifacts/599bbfbf9ca7f67a75c299331047cc51d7f06acf/lib/libhighs.so (unknown line)
Highs_run at /home/runner/.julia/packages/HiGHS/p35Je/src/gen/libhighs.jl:328 [inlined]
_Highs_run_workaround_issue_316 at /home/runner/.julia/packages/HiGHS/p35Je/src/MOI_wrapper.jl:2253 [inlined]
#42 at /home/runner/.julia/packages/HiGHS/p35Je/src/MOI_wrapper.jl:2300 [inlined]
disable_sigint at ./c.jl:473
optimize! at /home/runner/.julia/packages/HiGHS/p35Je/src/MOI_wrapper.jl:2300
optimize! at /home/runner/.julia/packages/MathOptInterface/Q3V1z/src/Bridges/bridge_optimizer.jl:367 [inlined]
optimize! at /home/runner/.julia/packages/MathOptInterface/Q3V1z/src/MathOptInterface.jl:122 [inlined]
optimize! at /home/runner/.julia/packages/MathOptInterface/Q3V1z/src/Utilities/cachingoptimizer.jl:370
unknown function (ip: 0xe50d4c30)
_jl_invoke at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/gf.c:2897 [inlined]
ijl_apply_generic at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/gf.c:3079
#optimize!#105 at /home/runner/.julia/packages/JuMP/0tD10/src/optimizer_interface.jl:610
optimize! at /home/runner/.julia/packages/JuMP/0tD10/src/optimizer_interface.jl:560
unknown function (ip: 0xe50bf800)
_jl_invoke at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/gf.c:2897 [inlined]
ijl_apply_generic at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/gf.c:3079
test_highs_qp_mps_32bit at /home/runner/work/LinearDecisionRules.jl/LinearDecisionRules.jl/test/runtests.jl:2795
unknown function (ip: 0xe50278a6)
_jl_invoke at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/gf.c:2897 [inlined]
ijl_apply_generic at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/gf.c:3079
macro expansion at /home/runner/work/LinearDecisionRules.jl/LinearDecisionRules.jl/test/runtests.jl:24 [inlined]
macro expansion at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/usr/share/julia/stdlib/v1.10/Test/src/Test.jl:1582 [inlined]
runtests at /home/runner/work/LinearDecisionRules.jl/LinearDecisionRules.jl/test/runtests.jl:24
unknown function (ip: 0xe50204e6)
_jl_invoke at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/gf.c:2897 [inlined]
ijl_apply_generic at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/gf.c:3079
jl_apply at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/julia.h:1982 [inlined]
do_call at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/interpreter.c:126
eval_value at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/interpreter.c:223
eval_stmt_value at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/interpreter.c:174 [inlined]
eval_body at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/interpreter.c:617
jl_interpret_toplevel_thunk at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/interpreter.c:775
jl_toplevel_eval_flex at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/toplevel.c:934
jl_toplevel_eval_flex at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/toplevel.c:877
ijl_toplevel_eval at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/toplevel.c:943
ijl_toplevel_eval_in at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/toplevel.c:985
eval at ./boot.jl:385 [inlined]
include_string at ./loading.jl:2160
_jl_invoke at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/gf.c:2878 [inlined]
ijl_apply_generic at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/gf.c:3079
_include at ./loading.jl:2220
include at ./client.jl:487
unknown function (ip: 0xe4fe6100)
_jl_invoke at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/gf.c:2897 [inlined]
ijl_apply_generic at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/gf.c:3079
jl_apply at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/julia.h:1982 [inlined]
do_call at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/interpreter.c:126
eval_value at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/interpreter.c:223
eval_stmt_value at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/interpreter.c:174 [inlined]
eval_body at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/interpreter.c:617
jl_interpret_toplevel_thunk at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/interpreter.c:775
jl_toplevel_eval_flex at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/toplevel.c:934
jl_toplevel_eval_flex at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/toplevel.c:877
ijl_toplevel_eval at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/toplevel.c:943
ijl_toplevel_eval_in at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/toplevel.c:985
eval at ./boot.jl:385 [inlined]
exec_options at ./client.jl:289
_start at ./client.jl:550
jfptr__start_82843 at /opt/hostedtoolcache/julia/1.10.11/x86/lib/julia/sys.so (unknown line)
_jl_invoke at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/gf.c:2878 [inlined]
ijl_apply_generic at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/gf.c:3079
jl_apply at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/julia.h:1982 [inlined]
true_main at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/jlapi.c:582
jl_repl_entrypoint at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/src/jlapi.c:731
main at /cache/build/builder-amdci4-5/julialang/julia-release-1-dot-10/cli/loader_exe.c:58
unknown function (ip: 0xf602cc74)
__libc_start_main at /lib32/libc.so.6 (unknown line)
unknown function (ip: 0x80490cf)
Allocations: 8436898 (Pool: 8433998; Big: 2900); GC: 25

[odow]

x-ref #769

Maybe I need to try #769 (comment)

We currently skip i686-linux in HiGHS.jl

https://github.com/jump-dev/HiGHS.jl/blob/ac47dfdc5900cbdb8b21ade813d99b606b06baca/.github/workflows/ci.yml#L25-L33

Edit: I've opened jump-dev/HiGHS.jl#331

[jajhall]

@joaquimg, we can't start to look at this with the information you've given us. Could you at least give us information to identify the line where the segfault occurs - a valgrind trace perhaps? Even this is probably not enough.

We don't have access to a 32-bit machine to investigate this, so we'd have to try to create a 32-bit virtual machine, and I have to think about the value of devoting resources to support such a niche architecture.

[joaquimg]

Thanks @jajhall ,
This was found in automated testing.
I do not have access to 32-bit, and I did all tracking in GitHub CI.
I have no particular interest in this architecture, so if highs is also not particularly interested in 32bits we can consider closing.

However, I would recommend a tier system like julia's:
https://julialang.org/downloads/support/
(sorry if already exists)
To clarify to user that 32bit is tier2 (or 3)

[jajhall]

However, I would recommend a tier system like julia's:\nhttps://julialang.org/downloads/support/\n(sorry if already exists)\nTo clarify to user that 32bit is tier2 (or 3)

Thanks, a summary in this form of what users can expect from HiGHS would be good to offer @galabovaa

[jajhall]

However, I would recommend a tier system like julia's:\nhttps://julialang.org/downloads/support/\n(sorry if already exists)\nTo clarify to user that 32bit is tier2 (or 3)

Thanks, a summary in this form of what users can expect from HiGHS would be good to offer @galabovaa

Together with a healthy warning about compiling highs for 32-bit doubles! 😅

[filikat]

I think this reveals another issue. The error is due to an uncaught exception in HiGHS, and this should not happen. The calls to IPX, HiPO and pdlp are wrapped in try-catch blocks (in HighsSolve.cpp), so that HiGHS can catch any exception thrown. But the QP solver and simplex do not have a try-catch block, so an exception can escape, leading to the abnormal termination of HiGHS (and potential untold damage in downstream interfaces).

[jajhall]

Fair point