Core was generated by `postgres: tomas test2 [local] SELECT                               '.
Program terminated with signal SIGSEGV, Segmentation fault.
#0  MemoryContextResetOnly (context=0x0) at mcxt.c:158
158             if (!context->isReset)
(gdb) bt
#0  MemoryContextResetOnly (context=0x0) at mcxt.c:158
#1  0x0000560f622f07b3 in tuplesort_reset (state=0x560f632e56a0) at tuplesort.c:1391
#2  0x0000560f620a2d17 in ExecIncrementalSort (pstate=0x560f632e1890) at nodeIncrementalSort.c:280
#3  0x0000560f6207d5da in ExecProcNode (node=0x560f632e1890) at ../../../src/include/executor/executor.h:239
#4  ExecutePlan (execute_once=<optimized out>, dest=0x560f632daf28, direction=<optimized out>, numberTuples=0, sendTuples=<optimized out>, operation=CMD_SELECT, use_parallel_mode=<optimized out>, planstate=0x560f632e1890, estate=0x560f632e1680) at execMain.c:1721
#5  standard_ExecutorRun (queryDesc=0x560f63233f60, direction=<optimized out>, count=0, execute_once=<optimized out>) at execMain.c:361
#6  0x0000560f621b8cfc in PortalRunSelect (portal=portal@entry=0x560f63277e40, forward=forward@entry=1 '\001', count=0, count@entry=9223372036854775807, dest=dest@entry=0x560f632daf28) at pquery.c:932
#7  0x0000560f621ba136 in PortalRun (portal=portal@entry=0x560f63277e40, count=count@entry=9223372036854775807, isTopLevel=isTopLevel@entry=1 '\001', run_once=run_once@entry=1 '\001', dest=dest@entry=0x560f632daf28, altdest=altdest@entry=0x560f632daf28, 
    completionTag=0x7fffdd875ac0 "") at pquery.c:773
#8  0x0000560f621b60cb in exec_simple_query (query_string=0x560f63213820 "SELECT * FROM (SELECT * FROM t ORDER BY a) foo ORDER BY a, b;") at postgres.c:1120
#9  0x0000560f621b7df4 in PostgresMain (argc=<optimized out>, argv=argv@entry=0x560f63240678, dbname=<optimized out>, username=<optimized out>) at postgres.c:4144
#10 0x0000560f61ef56d1 in BackendRun (port=0x560f63236130) at postmaster.c:4412
#11 BackendStartup (port=0x560f63236130) at postmaster.c:4084
#12 ServerLoop () at postmaster.c:1757
#13 0x0000560f62148242 in PostmasterMain (argc=3, argv=0x560f6320e3e0) at postmaster.c:1365
#14 0x0000560f61ef66b7 in main (argc=3, argv=0x560f6320e3e0) at main.c:228