<div dir="ltr">Hello Marc & SCIP users,<div><br></div><div>Thank you again for your kind help.</div><div><br></div><div>I have reformulated my problem a bit and tried multiple solvers on the LP file. At the end of the message you can find what I get using 4 different linear solvers: they all appear to report infeasibility.</div><div><br></div><div>When I run MinIISC on the problem, I get the output below, for which I still do not understand where/how to find the infeasible constraints. I can attach the LP file if need be, any clarification/suggestion is most welcome.</div><div><br></div><div><font face="monospace">MinIISC Output</font></div><div><font face="monospace">==============</font></div><div><br></div><div><font face="monospace">C:\Users\USER\MyProjects>miniisc.exe CPD_infeasible_114.lp<br>Finding a minimum IIS cover using a set covering approach.<br>Implemented by Marc Pfetsch, 2015<br><br>SCIP version 9.2.1 [precision: 8 byte] [memory: block] [mode: optimized] [LP solver: Soplex 7.1.3] [GitHash: 0d2d3c7c2d]<br>Copyright (c) 2002-2025 Zuse Institute Berlin (ZIB)<br><br>Input file: CPD_infeasible_114.lp<br>Problem name: CPD_infeasible_114<br><br>original problem has 3378 variables (0 bin, 0 int, 0 impl, 3378 cont) and 3530 constraints<br><br>Using reoptimization.<br><br>Optimally solving master problem ...<br> time | niter |nconss | nvars |master|totalnodes|oracle| ncuts | dualbound<br> 0.0s| 1 | 21 | 5769 | 0.0s| 1 | 0.0s| 21 | 1.400000e+01<br><br>SCIP Status : problem is solved [optimal solution found]<br>Solving Time (sec) : 0.00<br>Solving Nodes : 1 (total of 1 nodes in 2 runs)<br>Primal Bound : +1.40000000000000e+01<br>Dual Bound : +1.40000000000000e+01<br>Gap : 0.00 %<br><br><br>SCIP Status : problem is solved [optimal solution found]<br>Total Time : 0.00<br> solving : 0.00<br> master : 0.00 (included in solving)<br> oracle : 0.00 (included in solving)<br>Original Problem :<br> Problem name : CPD_infeasible_114<br> Variables : 5758 (5769 binary, 0 integer, 0 implicit integer, 0 continuous)<br> Constraints : 1 initial, 21 maximal<br> Objective sense : minimize<br>Presolved Problem :<br> Problem name : CPD_infeasible_114<br> Variables : 5758 (5758 binary, 0 integer, 0 implicit integer, 0 continuous)<br> Constraints : 8 initial, 21 maximal<br>Constraints : Number MaxNumber #Separate #Propagate #EnfoLP #EnfoPS #Check #ResProp Cutoffs DomReds Cuts Applied Conss Children<br> benders : 1 1 0 0 0 0 0 0 0 0 0 0 21 0<br>Constraint Timings : TotalTime SetupTime Separate Propagate EnfoLP EnfoPS Check ResProp SB-Prop<br> benders : 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00<br>B&B Tree :<br> number of runs : 2<br> nodes (total) : 1<br>Solution :<br> Primal Bound : +1.40000000000000e+01<br> Dual Bound : +1.40000000000000e+01<br> Gap : 0.00 %</font></div><div><font face="monospace"><br></font></div><div><br></div><div><br></div><div>Solvers output on the original LP:</div><div><br></div><div><div><span style="font-family:monospace">HiGHS</span></div></div><div><font face="monospace">-----</font></div><div><font face="monospace"><br></font></div><div><font face="monospace">C:\Users\USER\MyProjects>highs.exe CPD_infeasible_114.lp --solution_file CPD_output_highs.txt --options_file=HiGHS_options.txt</font></div><div><font face="monospace"><br>Running HiGHS 1.9.0 (git hash: n/a): Copyright (c) 2024 HiGHS under MIT licence terms<br>LP CPD_infeasible_114 has 3530 rows; 3378 cols; 6409 nonzeros<br>Coefficient ranges:<br> Matrix [4e-04, 5e+00]<br> Cost [1e-06, 7e-01]<br> Bound [6e+00, 2e+07]<br> RHS [3e+02, 8e+05]<br>Presolving model<br>Problem status detected on presolve: Infeasible<br>Model name : CPD_infeasible_114<br>Model status : Infeasible<br>Objective value : 0.0000000000e+00<br>HiGHS run time : 0.01</font></div><div><br></div><div><br></div><div><div><font face="monospace">CLP</font></div><div><font face="monospace">---</font></div><br class="gmail-Apple-interchange-newline"></div><div><font face="monospace">C:\Users\USER\MyProjects>clp.exe CPD_infeasible_114.lp -max -presolve=on -dualS -solve -solu CPD_output_clp.txt</font></div><div><font face="monospace"><br>Coin LP version trunk, build Jun 8 2020<br>command line - clp.exe CPD_infeasible_114.lp -max -presolve=on -dualS -solve -solu CPD_output_clp.txt<br>Coin0009I CoinLpIO::readLp(): Maximization problem reformulated as minimization<br>Switching back to maximization to get correct duals etc<br>Presolve determined that the problem was infeasible with tolerance of 1e-08<br>Analysis indicates model infeasible or unbounded<br>1 infeasibilities<br>Analysis indicates model infeasible or unbounded<br>Perturbing problem by 0.001% of 0.19828445 - largest nonzero change 0.00010013401 ( 2618.646%) - largest zero change 0.00010005909<br>Primal infeasible - objective value 112802.83<br>PrimalInfeasible objective 112802.8313 - 7 iterations time 0.002<br>Presolve determined that the problem was infeasible with tolerance of 1e-08<br>Analysis indicates model infeasible or unbounded<br>1 infeasibilities<br>Analysis indicates model infeasible or unbounded<br>Perturbing problem by 0.001% of 0.19828445 - largest nonzero change 0.00010013401 ( 2618.646%) - largest zero change 0.00010005909<br>Primal infeasible - objective value 112832.03<br>PrimalInfeasible objective 112832.0327 - 0 iterations time 0.002</font></div><div><br></div><div><br></div><div><div><font face="monospace">GLPK</font></div><div><font face="monospace">----</font></div><br class="gmail-Apple-interchange-newline"></div><div><font face="monospace">C:\Users\USER\MyProjects>glpsol.exe --presol --dual --lp CPD_infeasible_114.lp<br>GLPSOL: GLPK LP/MIP Solver, v4.65<br>Parameter(s) specified in the command line:<br> --presol --dual --lp CPD_infeasible_114.lp<br>Reading problem data from 'CPD_infeasible_114.lp'...<br>3530 rows, 3378 columns, 6409 non-zeros<br>4677 lines were read<br>GLPK Simplex Optimizer, v4.65<br>3530 rows, 3378 columns, 6409 non-zeros<br>Preprocessing...<br>PROBLEM HAS NO PRIMAL FEASIBLE SOLUTION<br>Time used: 0.0 secs<br>Memory used: 2.6 Mb (2716244 bytes)</font></div><div><br></div><div><br></div><div><div><font face="monospace">SCIP</font></div><div><font face="monospace">----</font></div><br class="gmail-Apple-interchange-newline"></div><div><font face="monospace">C:\Users\USER\MyProjects>scip.exe -c "read CPD_infeasible_114.lp opt write solution CPD_output_scip.txt quit"</font></div><div><font face="monospace"><br>SCIP version 9.2.1 [precision: 8 byte] [memory: block] [mode: optimized] [LP solver: Soplex 7.1.3] [GitHash: 0d2d3c7c2d]<br>Copyright (c) 2002-2025 Zuse Institute Berlin (ZIB)<br><br>External libraries:<br> Soplex 7.1.3 Linear Programming Solver developed at Zuse Institute Berlin (<a href="http://soplex.zib.de">soplex.zib.de</a>) [GitHash: 60fd96f2]<br> CppAD 20180000.0 Algorithmic Differentiation of C++ algorithms developed by B. Bell (<a href="http://github.com/coin-or/CppAD">github.com/coin-or/CppAD</a>)<br> TinyCThread 1.2 small portable implementation of the C11 threads API (<a href="http://tinycthread.github.io">tinycthread.github.io</a>)<br> MPIR 3.0.0 Multiple Precision Integers and Rationals Library developed by W. Hart (<a href="http://mpir.org">mpir.org</a>)<br> ZIMPL 3.6.2 Zuse Institute Mathematical Programming Language developed by T. Koch (<a href="http://zimpl.zib.de">zimpl.zib.de</a>)<br> AMPL/MP 690e9e7 AMPL .nl file reader library (<a href="http://github.com/ampl/mp">github.com/ampl/mp</a>)<br> PaPILO 2.4.1 parallel presolve for integer and linear optimization (<a href="http://github.com/scipopt/papilo">github.com/scipopt/papilo</a>) (built with TBB) [GitHash: 11974394]<br> Nauty 2.8.8 Computing Graph Automorphism Groups by Brendan D. McKay (<a href="http://users.cecs.anu.edu.au/~bdm/nauty">users.cecs.anu.edu.au/~bdm/nauty</a>)<br> sassy 1.1 Symmetry preprocessor by Markus Anders (<a href="http://github.com/markusa4/sassy">github.com/markusa4/sassy</a>)<br> Ipopt 3.14.16 Interior Point Optimizer developed by A. Waechter <a href="http://et.al">et.al</a>. (<a href="http://github.com/coin-or/Ipopt">github.com/coin-or/Ipopt</a>)<br><br>reading user parameter file <scip.set><br><br><br>read problem <CPD_infeasible_114.lp><br>============<br><br>original problem has 3378 variables (0 bin, 0 int, 0 impl, 3378 cont) and 3530 constraints<br> 3530 constraints of type <linear><br>Reading Time: 0.00<br><br>LP Solver <Soplex 7.1.3>: barrier convergence tolerance cannot be set -- tolerance of SCIP and LP solver may differ<br>LP Solver <Soplex 7.1.3>: fastmip setting not available -- SCIP parameter has no effect<br>LP Solver <Soplex 7.1.3>: number of threads settings not available -- SCIP parameter has no effect<br>transformed problem has 3378 variables (0 bin, 0 int, 0 impl, 3378 cont) and 3530 constraints<br> 3530 constraints of type <linear><br><br>original problem has 6409 active (0.0537472%) nonzeros and 6409 (0.0537472%) check nonzeros<br><br>presolving:<br>constraint handler <linear> detected infeasibility<br><br>presolved problem has 2175 active (0.232015%) nonzeros and 2175 (0.232015%) check nonzeros<br><br>presolving (1 rounds: 1 fast, 0 medium, 0 exhaustive):<br> 2748 deleted vars, 2042 deleted constraints, 0 added constraints, 2335 tightened bounds, 0 added holes, 0 changed sides, 0 changed coefficients<br> 0 implications, 0 cliques<br>presolving detected infeasibility<br>Presolving Time: 0.00<br><br>SCIP Status : problem is solved [infeasible]<br>Solving Time (sec) : 0.00<br>Solving Nodes : 0<br>Primal Bound : -1.00000000000000e+20 (objective limit, 0 solutions)<br>Dual Bound : -1.00000000000000e+20<br>Gap : 0.00 %</font></div><div><br></div><div><br></div><div><br></div></div><br><div class="gmail_quote gmail_quote_container"><div dir="ltr" class="gmail_attr">On Wed, 26 Mar 2025 at 21:05, Marc Pfetsch <<a href="mailto:pfetsch@mathematik.tu-darmstadt.de">pfetsch@mathematik.tu-darmstadt.de</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><br>
<br>
Dear Andrea,<br>
<br>
I think that the program thinks that your instance is actually feasible. <br>
Thus, no constraint has to be removed (the primal bound is therefore 0).<br>
<br>
You can turn on more output by adding "#define SCIP_OUTPUT" a the top of <br>
minissc.c and/or benders.c. If you want even more output, you can add <br>
"#define SCIP_DEBUG".<br>
<br>
I hope this helps.<br>
<br>
Best<br>
<br>
Marc<br>
<br>
<br>
On 26/03/2025 20:33, Andrea Gavana wrote:<br>
> Hello Mark & SCIP users,<br>
> <br>
> I managed to compile MinIISC by dropping the ZLIb requirements.<br>
> <br>
> I am feeding it with an LP file containing a model I know to be <br>
> infeasible and I am getting the output I paste below. I am unclear <br>
> though how to interpret the output - what is MinIISC telling me? Where <br>
> do I find the offending constraints? Is there any way to output that <br>
> information in a file?<br>
> <br>
> My apologies if I am misunderstanding everything here.<br>
> <br>
> Andrea.<br>
> <br>
> <br>
> -----------------<br>
> Output of MinIISC<br>
> -----------------<br>
> <br>
> C:\Users\USER\MyProjects>miniisc.exe infeasible_118.lp -s scip.set<br>
> Finding a minimum IIS cover using a set covering approach.<br>
> Implemented by Marc Pfetsch, 2015<br>
> <br>
> SCIP version 9.2.1 [precision: 8 byte] [memory: block] [mode: optimized] <br>
> [LP solver: Soplex 7.1.3] [GitHash: 0d2d3c7c2d]<br>
> Copyright (c) 2002-2025 Zuse Institute Berlin (ZIB)<br>
> <br>
> reading user parameter file <scip.set> ...<br>
> <br>
> display/verblevel = 5<br>
> display/freq = 1<br>
> display/lpinfo = TRUE<br>
> Input file: infeasible_118.lp<br>
> Problem name: infeasible_118<br>
> <br>
> original problem has 3378 variables (0 bin, 0 int, 0 impl, 3378 cont) <br>
> and 3804 constraints<br>
> <br>
> Using reoptimization.<br>
> <br>
> Optimally solving master problem ...<br>
> time | niter |nconss | nvars |master|totalnodes|oracle| ncuts | <br>
> dualbound<br>
> <br>
> SCIP Status : problem is solved [optimal solution found]<br>
> Solving Time (sec) : 0.00<br>
> Solving Nodes : 0 (total of 0 nodes in 1 runs)<br>
> Primal Bound : +0.00000000000000e+00<br>
> Dual Bound : -1.00000000000000e+20<br>
> Gap : infinite<br>
> <br>
> <br>
> SCIP Status : problem is solved [optimal solution found]<br>
> Total Time : 0.00<br>
> solving : 0.00<br>
> master : 0.00 (included in solving)<br>
> oracle : 0.00 (included in solving)<br>
> Original Problem :<br>
> Problem name : infeasible_118<br>
> Variables : 6331 (6331 binary, 0 integer, 0 implicit integer, <br>
> 0 continuous)<br>
> Constraints : 1 initial, 0 maximal<br>
> Objective sense : minimize<br>
> Presolved Problem :<br>
> Problem name : infeasible_118<br>
> Variables : 6331 (6331 binary, 0 integer, 0 implicit integer, <br>
> 0 continuous)<br>
> Constraints : 0 initial, 0 maximal<br>
> Constraints : Number MaxNumber #Separate #Propagate <br>
> #EnfoLP #EnfoPS #Check #ResProp Cutoffs DomReds <br>
> Cuts Applied Conss Children<br>
> benders : 1 1 0 0 <br>
> 0 0 0 0 0 0 0 <br>
> 0 0 0<br>
> Constraint Timings : TotalTime SetupTime Separate Propagate <br>
> EnfoLP EnfoPS Check ResProp SB-Prop<br>
> benders : 0.00 0.00 0.00 0.00 <br>
> 0.00 0.00 0.00 0.00 0.00<br>
> B&B Tree :<br>
> number of runs : 1<br>
> nodes (total) : 0<br>
> Solution :<br>
> Primal Bound : +0.00000000000000e+00<br>
> Dual Bound : -1.00000000000000e+20<br>
> Gap : infinite<br>
> <br>
> <br>
> <br>
> On Wed, 26 Mar 2025 at 08:29, Andrea Gavana <<a href="mailto:andrea.gavana@gmail.com" target="_blank">andrea.gavana@gmail.com</a> <br>
> <mailto:<a href="mailto:andrea.gavana@gmail.com" target="_blank">andrea.gavana@gmail.com</a>>> wrote:<br>
> <br>
> Hello Marc,<br>
> <br>
> Thank you for your super-quick answer, I appreciate it very much.<br>
> <br>
> I have removed the READLINE requirement as you suggested. While the<br>
> compilation process finishes (100%), the linker fails without any<br>
> meaningful message that I can see (even using --verbose as a linker<br>
> argument).<br>
> <br>
> It simply says: collect2.exe: error: ld returned 5 exit status<br>
> <br>
> Below is the ending part of the linking process, obtained via the<br>
> --verbose input to the linker. I have a build log with the entirety<br>
> of the compilation process, but it's 500 kb and I am not sure if<br>
> it's frowned upon to attach these types of files to the mailing list<br>
> or not.<br>
> <br>
> I cannot see any compilation error, only some warnings like these:<br>
> <br>
> C:\Users\USER\Downloads\scipoptsuite-9.2.1\scipoptsuite-9.2.1\scip\src\blockmemshell\memory.c:2411:14: warning: ISO C does not support the 'I64' ms_printf length modifier [-Wformat=]<br>
> C:/Users/USER/Downloads/scipoptsuite-9.2.1/scipoptsuite-9.2.1/scip/src/scip/def.h:106:20: warning: redundant redeclaration of 'int _stricmp(const char*, const char*)' in same scope [-Wredundant-decls]<br>
> <br>
> They seem harmless (to me).<br>
> <br>
> I am using MinGW64 11.2.0 from WinLibs, and until now I have never<br>
> had any issue in building C programs or C extensions using it...<br>
> <br>
> Any suggestion is most welcome, thank you in advance.<br>
> <br>
> <br>
> [100%] Linking CXX shared library ..\..\bin\libscip.dll<br>
> <br>
> Using built-in specs.<br>
> COLLECT_GCC=C:\Users\USER\Tools\MinGW64\bin\g++.exe<br>
> COLLECT_LTO_WRAPPER=c:/users/USER/tools/mingw64/bin/../libexec/gcc/x86_64-w64-mingw32/11.2.0/lto-wrapper.exe<br>
> OFFLOAD_TARGET_NAMES=nvptx-none<br>
> Target: x86_64-w64-mingw32<br>
> Configured with: ../configure<br>
> --prefix=/R/winlibs64_stage/inst_gcc-11.2.0/share/gcc<br>
> --build=x86_64-w64-mingw32 --host=x86_64-w64-mingw32<br>
> --enable-offload-targets=nvptx-none --with-pkgversion='MinGW-W64<br>
> x86_64-ucrt-posix-seh, built by Brecht Sanders' --with-tune=generic<br>
> --enable-checking=release --enable-threads=posix<br>
> --disable-sjlj-exceptions --disable-libunwind-exceptions<br>
> --disable-serial-configure --disable-bootstrap --enable-host-shared<br>
> --enable-plugin --disable-default-ssp --disable-rpath<br>
> --enable-libstdcxx-pch --enable-libstdcxx-time=yes<br>
> --disable-libstdcxx-debug --disable-version-specific-runtime-libs<br>
> --with-stabs --disable-symvers<br>
> --enable-languages=c,c++,fortran,lto,objc,obj-c++,d,jit<br>
> --disable-gold --disable-nls --disable-stage1-checking<br>
> --disable-win32-registry --disable-multilib --enable-ld<br>
> --enable-libquadmath --enable-libada --enable-libssp<br>
> --enable-libstdcxx --enable-lto --enable-fully-dynamic-string<br>
> --enable-libgomp --enable-graphite --enable-mingw-wildcard<br>
> --with-mpc=/d/Prog/winlibs64_stage/custombuilt<br>
> --with-mpfr=/d/Prog/winlibs64_stage/custombuilt<br>
> --with-gmp=/d/Prog/winlibs64_stage/custombuilt<br>
> --with-isl=/d/Prog/winlibs64_stage/custombuilt<br>
> --enable-install-libiberty --enable-__cxa_atexit<br>
> --without-included-gettext --with-diagnostics-color=auto<br>
> --enable-clocale=generic --with-libiconv --with-system-zlib<br>
> --with-build-sysroot=/R/winlibs64_stage/gcc-11.2.0/build_mingw/mingw-w64 CFLAGS=-I/d/Prog/winlibs64_stage/custombuilt/include/libdl-win32<br>
> Thread model: posix<br>
> Supported LTO compression algorithms: zlib zstd<br>
> gcc version 11.2.0 (MinGW-W64 x86_64-ucrt-posix-seh, built by Brecht<br>
> Sanders)<br>
> COMPILER_PATH=c:/users/USER/tools/mingw64/bin/../libexec/gcc/x86_64-w64-mingw32/11.2.0/;c:/users/USER/tools/mingw64/bin/../libexec/gcc/;c:/users/USER/tools/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/11.2.0/../../../../x86_64-w64-mingw32/bin/<br>
> LIBRARY_PATH=c:/users/USER/tools/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/11.2.0/;c:/users/USER/tools/mingw64/bin/../lib/gcc/;c:/users/USER/tools/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/11.2.0/../../../../x86_64-w64-mingw32/lib/../lib/;c:/users/USER/tools/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/11.2.0/../../../../lib/;c:/users/USER/tools/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/11.2.0/../../../../x86_64-w64-mingw32/lib/;c:/users/USER/tools/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/11.2.0/../../../<br>
> COLLECT_GCC_OPTIONS='-Wno-psabi' '-O3' '-D' 'NDEBUG' '-v' '-v'<br>
> '-shared' '-o' '..\..\bin\libscip.dll' '-shared-libgcc'<br>
> '-mtune=generic' '-march=x86-64' '-dumpdir' '..\..\bin\libscip.dll.'<br>
> c:/users/USER/tools/mingw64/bin/../libexec/gcc/x86_64-w64-mingw32/11.2.0/collect2.exe -plugin c:/users/USER/tools/mingw64/bin/../libexec/gcc/x86_64-w64-mingw32/11.2.0/liblto_plugin.dll -plugin-opt=c:/users/USER/tools/mingw64/bin/../libexec/gcc/x86_64-w64-mingw32/11.2.0/lto-wrapper.exe -plugin-opt=-fresolution=C:\Users\USER\AppData\Local\Temp\ccQoBFst.res -plugin-opt=-pass-through=-lmingw32 -plugin-opt=-pass-through=-lgcc_s -plugin-opt=-pass-through=-lgcc -plugin-opt=-pass-through=-lmoldname -plugin-opt=-pass-through=-lmingwex -plugin-opt=-pass-through=-lmsvcrt -plugin-opt=-pass-through=-lkernel32 -plugin-opt=-pass-through=-lpthread -plugin-opt=-pass-through=-ladvapi32 -plugin-opt=-pass-through=-lshell32 -plugin-opt=-pass-through=-luser32 -plugin-opt=-pass-through=-lkernel32 -plugin-opt=-pass-through=-lmingw32 -plugin-opt=-pass-through=-lgcc_s -plugin-opt=-pass-through=-lgcc -plugin-opt=-pass-through=-lmoldname -plugin-opt=-pass-through=-lmingwex -plugin-opt=-pass-through=-lmsvcrt -plugin-opt=-pass-through=-lkernel32 -m i386pep --shared -Bdynamic -e DllMainCRTStartup --enable-auto-image-base -o ..\..\bin\libscip.dll c:/users/USER/tools/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/11.2.0/../../../../x86_64-w64-mingw32/lib/../lib/dllcrt2.o c:/users/USER/tools/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/11.2.0/crtbegin.o -Lc:/users/USER/tools/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/11.2.0 -Lc:/users/USER/tools/mingw64/bin/../lib/gcc -Lc:/users/USER/tools/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/11.2.0/../../../../x86_64-w64-mingw32/lib/../lib -Lc:/users/USER/tools/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/11.2.0/../../../../lib -Lc:/users/USER/tools/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/11.2.0/../../../../x86_64-w64-mingw32/lib -Lc:/users/USER/tools/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/11.2.0/../../.. @C:\Users\USER\AppData\Local\Temp\cc8OocJM -lmingw32 -lgcc_s -lgcc -lmoldname -lmingwex -lmsvcrt -lkernel32 -lpthread -ladvapi32 -lshell32 -luser32 -lkernel32 -lmingw32 -lgcc_s -lgcc -lmoldname -lmingwex -lmsvcrt -lkernel32 c:/users/USER/tools/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/11.2.0/crtend.o<br>
> collect2.exe: error: ld returned 5 exit status<br>
> mingw32-make[3]: ***<br>
> [scip\src\CMakeFiles\libscip.dir\build.make:6589: bin/libscip.dll]<br>
> Error 1<br>
> mingw32-make[3]: *** Deleting file 'bin/libscip.dll'<br>
> mingw32-make[2]: *** [CMakeFiles\Makefile2:2114:<br>
> scip/src/CMakeFiles/libscip.dir/all] Error 2<br>
> mingw32-make[1]: *** [CMakeFiles\Makefile2:2707:<br>
> scip/applications/MinIISC/CMakeFiles/miniisc.dir/rule] Error 2<br>
> mingw32-make: *** [makefile:1022: miniisc] Error 2<br>
> <br>
> <br>
> On Tue, 25 Mar 2025 at 22:35, Marc Pfetsch<br>
> <<a href="mailto:pfetsch@mathematik.tu-darmstadt.de" target="_blank">pfetsch@mathematik.tu-darmstadt.de</a><br>
> <mailto:<a href="mailto:pfetsch@mathematik.tu-darmstadt.de" target="_blank">pfetsch@mathematik.tu-darmstadt.de</a>>> wrote:<br>
> <br>
> <br>
> <br>
> Hi Andrea,<br>
> <br>
> SCIP does not yet support computing IISs for LPs yet.<br>
> <br>
> MinIISC is for computing a smallest number of constraints that<br>
> have to<br>
> be removed in order to obtain a feasible problem. (In some<br>
> sense, this<br>
> is dual to computing IISs.)<br>
> <br>
> However, it is not hard to compute some IISs (although not<br>
> necessarily<br>
> one of smallest size), by computing a vertex of the alternative<br>
> polyhedron ({y: A^T y = 0, b^T y = -1, y \geq 0} for the original<br>
> infeasible system Ax \leq b.) [The MinIISC code also builds this<br>
> polyhedron and you might want to modify the code to output an IIS.]<br>
> <br>
> For your installation you should install "libreadline-dev" or use<br>
> "-DREADLINE=off" as an argument to the cmake call.<br>
> <br>
> Best<br>
> <br>
> Marc<br>
> <br>
> On 25/03/2025 12:39, Andrea Gavana wrote:<br>
> > Hello SCIP Users,<br>
> ><br>
> > I am a newbie with SCIP - I have used it a few times for<br>
> simple MIPs and<br>
> > always using the available binaries for Windows 64 bit. I<br>
> have never<br>
> > compiled it from source.<br>
> ><br>
> > I am now looking for ways to detect IIS in some of my standard,<br>
> > continuous LPs (no MIPs). My understanding is that the MinIISC<br>
> > application can be used for that purpose.<br>
> ><br>
> > Unfortunately, there appear not to be any precompiled<br>
> binaries for<br>
> > MinIISC (or any other application that is not SCIP). Or at<br>
> least I<br>
> > couldn't find it anywhere.<br>
> ><br>
> > So I have tried to follow the instructions on building SCIP<br>
> and MinIISC<br>
> > from the SCIP website, using CMake on Windows and the MinGW64<br>
> toolchain<br>
> > (gcc for Windows) 11.2.0. I explicitly specify MinGW Makefiles.<br>
> ><br>
> > The CMake configure action ends like this:<br>
> ><br>
> > The following OPTIONAL packages have been found:<br>
> ><br>
> ><br>
> > * SOPLEX<br>
> ><br>
> > * PkgConfig<br>
> ><br>
> ><br>
> > -- The following REQUIRED packages have been found:<br>
> ><br>
> ><br>
> > * Readline<br>
> ><br>
> > * SCIP<br>
> ><br>
> > * Threads<br>
> ><br>
> > * ZLIB<br>
> ><br>
> ><br>
> > -- The following OPTIONAL packages have not been found:<br>
> ><br>
> ><br>
> > * Boost (required version >= 1.65.0)<br>
> ><br>
> > * PAPILO<br>
> ><br>
> > * ZIMPL (required version >= 3.5.0)<br>
> ><br>
> > * IPOPT (required version >= 3.12.0)<br>
> ><br>
> > * WORHP<br>
> ><br>
> > * CRITERION<br>
> ><br>
> > * GSL (required version >= 2.0)<br>
> ><br>
> > * GMP<br>
> ><br>
> > * CLIQUER<br>
> ><br>
> ><br>
> > Configuring done<br>
> ><br>
> ><br>
> ><br>
> > After the "generate" from CMake, I naively attempted this:<br>
> ><br>
> > cmake.exe --build build --target miniisc<br>
> ><br>
> > I get this:<br>
> ><br>
> ><br>
> C:\Users\XXXX\scipoptsuite-9.2.1\scip\src\scip\dialog.c:48:10:<br>
> fatal<br>
> > error: readline/readline.h: No such file or directory<br>
> > 48 | #include <readline/readline.h><br>
> > | ^~~~~~~~~~~~~~~~~~~~~<br>
> > compilation terminated.<br>
> > mingw32-make[3]: ***<br>
> [scip\src\CMakeFiles\libscip.dir\build.make:3751:<br>
> > scip/src/CMakeFiles/libscip.dir/scip/dialog.c.obj] Error 1<br>
> > mingw32-make[2]: *** [CMakeFiles\Makefile2:2114:<br>
> > scip/src/CMakeFiles/libscip.dir/all] Error 2<br>
> > mingw32-make[1]: *** [CMakeFiles\Makefile2:2707:<br>
> > scip/applications/MinIISC/CMakeFiles/miniisc.dir/rule] Error 2<br>
> > mingw32-make: *** [makefile:1022: miniisc] Error 2<br>
> ><br>
> > I do have a readline-kind-of for Windows, that I obtained<br>
> > from mingw-w64-x86_64-readline, but I guess I must be doing<br>
> something<br>
> > wrong somewhere. I am not an expert in compiling packages, so<br>
> I am kind<br>
> > of lost here.<br>
> ><br>
> > I assume there aren't many people having a pre-compiled<br>
> executable for MinIISC on Windows, but if anyone does, please do<br>
> let me know - I'd be rather interested in giving it a try using<br>
> some LP files I already have. Or any other suggestion you may<br>
> have to help me fix the build issue would be most appreciated.<br>
> ><br>
> ><br>
> > Thank you in advance.<br>
> ><br>
> ><br>
> > Andrea.<br>
> ><br>
> ><br>
> ><br>
> ><br>
> > _______________________________________________<br>
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</blockquote></div>