Merge branch '3911-fix-scip-src-scip-lp-c-11417-scip_retcode-lplexdualsimplex-scip_lp-scip_set-scip_stat-unsigned-int' into 'v92-bugfix'

Resolve "scip/src/scip/lp.c:11417: SCIP_RETCODE lpLexDualSimplex(SCIP_LP *, SCIP_SET *, SCIP_STAT *, unsigned int, unsigned int, unsigned int *): Assertion `SCIPlpiIsOptimal(lp->lpi)' failed"

See merge request integer/scip!3843

Author: DominikKamp

CHANGELOG

@@ -9,6 +9,7 @@ Fixed bugs
 - avoid hashmap key error in removal of doubletons and singletons in dual presolve of setppc constraints by skipping tripleton locks
 - when upgrading to xor constraint require parity variable to be enforced integral
 - provide the depth of the applied effective root with SCIPtreeGetEffectiveRootDepth() to avert invalid globalization of constraint set changes
+- disable objective limit during lexicographic dual minimization to keep feasibility status
 
 Build system
 ------------

check/CMakeLists.txt

@@ -511,6 +511,7 @@ set(pairs_Issue
     # "instances/Issue/3842.cip\;-16812.7692740365\;default"
     "instances/Issue/3870.cip\;5133546551065818\;default"
     "instances/Issue/3908.cip\;-20317.1313131313\;subrestart"
+    "instances/Issue/3911.cip\;-30386.2338470598\;lexdual"
 )
 
 #

check/coverage/settings/lexdual.set

@@ -0,0 +1,2 @@
+lp/lexdualalgo = TRUE
+lp/lexdualstalling = FALSE

check/instances/Issue/3911.cip

@@ -0,0 +1,45 @@
+STATISTICS
+  Problem name     : seed
+  Variables        : 19 (0 binary, 10 integer, 0 implicit integer, 9 continuous)
+  Constraints      : 0 initial, 17 maximal
+OBJECTIVE
+  Sense            : minimize
+VARIABLES
+  [integer] <x3>: obj=0, original bounds=[-200,200]
+  [integer] <x19>: obj=0, original bounds=[-200,200]
+  [integer] <x16>: obj=45, original bounds=[-200,200]
+  [integer] <x15>: obj=-67, original bounds=[-200,200]
+  [integer] <x14>: obj=35, original bounds=[-200,200]
+  [integer] <x12>: obj=33, original bounds=[-200,200]
+  [integer] <x10>: obj=45, original bounds=[-200,200]
+  [integer] <x1>: obj=-73, original bounds=[-200,200]
+  [integer] <x0>: obj=46, original bounds=[-200,200]
+  [integer] <x6>: obj=0, original bounds=[-200,200]
+  [continuous] <x18>: obj=82, original bounds=[-200,200]
+  [continuous] <x13>: obj=81, original bounds=[-200,200]
+  [continuous] <x2>: obj=-66, original bounds=[-200,200]
+  [continuous] <x11>: obj=0, original bounds=[-200,200]
+  [continuous] <x4>: obj=0, original bounds=[-200,200]
+  [continuous] <x5>: obj=0, original bounds=[-200,200]
+  [continuous] <x17>: obj=-63, original bounds=[-200,200]
+  [continuous] <x7>: obj=43, original bounds=[-200,200]
+  [continuous] <x8>: obj=0, original bounds=[-200,200]
+CONSTRAINTS
+  [linear] <_C1>:  +53.04<x3>[I] +71.89<x19>[I] -0.51<x16>[I] +66.37<x15>[I] -16.04<x14>[I] +0.24<x12>[I] -87.12<x10>[I] +82.18<x1>[I] +76.74<x0>[I] -12.47<x6>[I] -2.55<x18>[C] -48.08<x13>[C] -11.36<x2>[C] -92.81<x11>[C] -73.04<x4>[C] -52.83<x5>[C] -79.84<x17>[C] +60.41<x7>[C] +88.47<x8>[C] <= 11066.88;
+  [linear] <_C6>:  -21<x3>[I] +87<x19>[I] +48<x16>[I] +20<x15>[I] +62<x14>[I] -2<x12>[I] -17<x10>[I] -93<x1>[I] -35<x0>[I] +7<x6>[I] +78<x18>[C] -82<x13>[C] +72<x2>[C] -12<x11>[C] -64<x4>[C] -69<x5>[C] +81<x17>[C] +10<x7>[C] -82<x8>[C] <= 9556;
+  [linear] <_C32>:  -53.41<x3>[I] +31.39<x19>[I] +46.55<x16>[I] -67.59<x15>[I] -90.57<x14>[I] +85.21<x12>[I] +28.46<x10>[I] -6.49<x1>[I] -13.31<x0>[I] -46.45<x6>[I] -82.12<x18>[C] +6.86<x13>[C] -24.06<x2>[C] -81.35<x11>[C] +87.27<x4>[C] +58.41<x5>[C] +31.95<x17>[C] +8.98<x7>[C] +83.06<x8>[C] >= 4921.49;
+  [linear] <_C38>:  -28<x3>[I] -43<x19>[I] +52<x16>[I] +20<x15>[I] +90<x14>[I] -91<x12>[I] +30<x10>[I] -34<x1>[I] +16<x0>[I] +43<x6>[I] +41<x18>[C] -6<x13>[C] +72<x2>[C] -71<x11>[C] -41<x4>[C] +15<x5>[C] +76<x17>[C] +70<x7>[C] -92<x8>[C] >= -5663;
+  [linear] <_C44>:  -14<x3>[I] -3<x19>[I] -64<x16>[I] -32<x15>[I] -58<x14>[I] +24<x12>[I] -37<x10>[I] +58<x1>[I] -60<x0>[I] +<x6>[I] -8<x18>[C] +51<x13>[C] +62<x2>[C] -79<x11>[C] -54<x4>[C] +20<x5>[C] +59<x17>[C] -70<x7>[C] -79<x8>[C] <= 12294;
+  [linear] <_C47>:  +21.94<x3>[I] -98.5<x19>[I] +73<x16>[I] +76.23<x15>[I] -46.96<x14>[I] -43.12<x12>[I] -97.32<x10>[I] +65.37<x1>[I] +65.58<x0>[I] +42.61<x6>[I] +94.21<x18>[C] -32.18<x13>[C] +48.12<x2>[C] +48.61<x11>[C] +70.34<x4>[C] +60.9<x5>[C] -85.59<x17>[C] -11.59<x7>[C] -21.49<x8>[C] >= 15621.22;
+  [linear] <_C48>:  -62.23<x3>[I] +67.46<x19>[I] +59.55<x16>[I] +59.76<x15>[I] +10.48<x14>[I] -26.57<x12>[I] -71.3<x10>[I] -35.85<x1>[I] +16.37<x0>[I] -44.44<x6>[I] -48.01<x18>[C] -94.01<x13>[C] +73.95<x2>[C] +74.94<x11>[C] +11.76<x4>[C] -0.21<x5>[C] -66.46<x17>[C] +86.43<x7>[C] +47.03<x8>[C] <= 19685.14;
+  [linear] <_C59>:  +59.47<x3>[I] +59.93<x19>[I] +40.29<x16>[I] +61.57<x15>[I] +6<x14>[I] -27.57<x12>[I] -52.34<x10>[I] -19.45<x1>[I] +92.08<x0>[I] +10.32<x6>[I] +72.88<x18>[C] +42.05<x13>[C] -61.62<x2>[C] +49.14<x11>[C] +32.13<x4>[C] +97.53<x5>[C] -45.31<x17>[C] +25.31<x7>[C] -23.03<x8>[C] >= 11872.66;
+  [linear] <_C61>:  -66.76<x3>[I] +82.7<x19>[I] -50.77<x16>[I] -5.3<x15>[I] -43.24<x14>[I] +73.53<x12>[I] -55.23<x10>[I] +31.59<x1>[I] -45.31<x0>[I] -51.18<x6>[I] +18.9<x18>[C] +17.72<x13>[C] -59.09<x2>[C] -60.31<x11>[C] -24.16<x4>[C] -90.31<x5>[C] -46.55<x17>[C] +62.58<x7>[C] -15.87<x8>[C] >= 8678.63;
+  [linear] <_C66>:  -12<x3>[I] +82.55<x19>[I] +1.05<x16>[I] -39.52<x15>[I] -44.51<x14>[I] -94.63<x12>[I] +74.86<x10>[I] -77.6<x1>[I] +31.22<x0>[I] -43.52<x6>[I] -35.44<x18>[C] -10.86<x13>[C] +47.88<x2>[C] -38.41<x11>[C] -98.63<x4>[C] +4.81<x5>[C] -42.14<x17>[C] -44.05<x7>[C] -7.14<x8>[C] == -9223.64;
+  [linear] <_C83>:  +67.95<x3>[I] +76.43<x19>[I] +5.63<x16>[I] -42.04<x15>[I] -64.43<x14>[I] -84.78<x12>[I] -70.51<x10>[I] +3.16<x1>[I] +99.36<x0>[I] +64.06<x6>[I] +81.17<x18>[C] -32.73<x13>[C] +18.55<x2>[C] -54.85<x11>[C] -4.52<x4>[C] -19.34<x5>[C] -96.89<x17>[C] +37.68<x7>[C] +72.83<x8>[C] >= 3720.45;
+  [linear] <_C94>:  -62<x3>[I] -14<x19>[I] -52<x16>[I] -86<x15>[I] +76<x14>[I] +18<x12>[I] +97<x10>[I] -25<x1>[I] -21<x0>[I] +13<x6>[I] -12<x18>[C] +31<x13>[C] -22<x2>[C] -97<x11>[C] -83<x4>[C] +40<x5>[C] +21<x17>[C] +84<x7>[C] -93<x8>[C] <= 13670;
+  [linear] <_C95>:  -37.72<x3>[I] +51.12<x19>[I] +33.21<x16>[I] +39.52<x15>[I] -91.45<x14>[I] -88<x12>[I] -53.76<x10>[I] +65.43<x1>[I] -39.93<x0>[I] +72.9<x6>[I] +15.76<x18>[C] -57.03<x13>[C] -15.17<x2>[C] +92.34<x11>[C] -61.19<x4>[C] +16.76<x5>[C] +39.63<x17>[C] -78.65<x7>[C] -20.09<x8>[C] <= 8911.73;
+  [linear] <_C102>:  +56.41<x3>[I] -46.57<x19>[I] -24.77<x16>[I] +16.42<x15>[I] +72.8<x14>[I] -8.17<x12>[I] -94.19<x10>[I] -4.95<x1>[I] -79.47<x0>[I] -22.21<x6>[I] -1.15<x18>[C] -34.4<x13>[C] -20.24<x2>[C] +91.42<x11>[C] -43.47<x4>[C] +21.22<x5>[C] -71.69<x17>[C] +58.94<x7>[C] == 10293.2797236906;
+  [linear] <_C104>:  -42.9<x3>[I] +3.88<x19>[I] -80.87<x16>[I] +80.69<x15>[I] -41.65<x14>[I] -86.74<x12>[I] +43.3<x10>[I] -29.08<x1>[I] +31.56<x0>[I] -88.53<x6>[I] -52.79<x18>[C] -36.67<x13>[C] -60.21<x2>[C] -74.1<x11>[C] +22.81<x4>[C] +53.38<x5>[C] -43.76<x17>[C] -12.69<x7>[C] -7.97<x8>[C] == -7087.74;
+  [linear] <_C119>:  +41<x3>[I] +12<x19>[I] -76<x16>[I] -73<x15>[I] -18<x14>[I] -52<x12>[I] +89<x10>[I] +58<x1>[I] +72<x0>[I] +8<x6>[I] -86<x18>[C] +51<x13>[C] +2<x2>[C] +82<x11>[C] -45<x4>[C] -49<x5>[C] +56<x17>[C] -75<x7>[C] -41<x8>[C] <= -14336;
+  [linear] <_C120>:  -42<x3>[I] -64<x19>[I] +58<x16>[I] -19<x15>[I] -96<x14>[I] -52<x12>[I] -69<x10>[I] -71<x1>[I] -63<x0>[I] +77<x6>[I] +53<x18>[C] -19<x13>[C] -20<x2>[C] +32<x11>[C] -30<x4>[C] +6<x5>[C] -64<x17>[C] -48<x7>[C] -48<x8>[C] >= -19452;
+END

src/scip/lp.c

@@ -10783,7 +10783,6 @@ SCIP_RETCODE lpLexDualSimplex(
    /* search for lexicographically minimal optimal solution */
    if( !lp->diving && !lp->probing && SCIPlpiIsOptimal(lp->lpi) )
    {
-      SCIP_Bool chooseBasic;
       SCIP_Real* primsol;
       SCIP_Real* dualsol;
       SCIP_Real* redcost;
@@ -10805,6 +10804,8 @@ SCIP_RETCODE lpLexDualSimplex(
       int* indrow;
       int* indallcol;
       int* indallrow;
+      SCIP_Bool chooseBasic;
+      SCIP_Bool success;
       int nDualDeg;
       int r, c;
       int cntcol;
@@ -10932,6 +10933,10 @@ SCIP_RETCODE lpLexDualSimplex(
       }
 #endif
 
+      /* disable objective limit */
+      SCIP_CALL( lpSetRealpar(lp, SCIP_LPPAR_OBJLIM, SCIPlpiInfinity(lp->lpi), &success) );
+      assert(success);
+
       /* perform lexicographic rounds */
       pos = -1;
       nruns = 0;
@@ -11170,7 +11175,7 @@ SCIP_RETCODE lpLexDualSimplex(
       SCIP_CALL( SCIPlpiChgSides(lp->lpi, lp->nlpirows, indallrow, oldlhs, oldrhs) );
       SCIP_CALL( SCIPlpiChgObj(lp->lpi, lp->nlpicols, indallcol, oldobj) );
 
-      /* resolve to update solvers internal data structures - should only produce few pivots - is this needed? */
+      /* resolve to update solvers internal data structures - should only produce few pivots */
       retcode = SCIPlpiSolveDual(lp->lpi);
       if( retcode == SCIP_LPERROR )
       {
@@ -11182,6 +11187,12 @@ SCIP_RETCODE lpLexDualSimplex(
          SCIP_CALL( retcode );
       }
       assert(SCIPlpiIsOptimal(lp->lpi));
+
+      /* reset objective limit */
+      SCIP_CALL( lpSetRealpar(lp, SCIP_LPPAR_OBJLIM, lp->lpiobjlim, &success) );
+      assert(success);
+
+      /* add LP iterations */
       SCIP_CALL( SCIPlpGetIterations(lp, &iterations) );
       lexIterations += iterations;