System.ValueTuple causes a StackOverflow when used in a large Dictionary. #8980
Description
Moved (and edited) this issue from the roslyn repo.
Summary: you add an empty Main method to the attached code, then compile it with csc.exe geocoords_stackoverflow.cs.txt. When you run the resulting executable, you get an overflow error (Process is terminated due to StackOverflowException.)
From discussion with @VSadov, we think this is a JIT issue rather than a compiler issue.
FYI @jkotas for triage. Thanks
@andras-ferencz commented on Tue Feb 28 2017
When using the new System.ValueTuple in a large Dictionary, I receive a stack overflow exception where as I do not with System.Tuple.
Dictionary<int, (double lat, double lon)> zipcodes = new Dictionary<int, (double lat, double lon)>() {{123,(18.180555,-66.749961)} }; works fine just for reference.
geocoords_stackoverflow.cs.txt
geocoords_worksfine.cs.txt
@jcouv commented on Tue Feb 28 2017
I'm able to see the repro file. The code causing stack overflow looks like this:
using System;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.RegularExpressions;
using System.Net.Mail;
namespace HAL
{
public static partial class geo
{
public static Dictionary<int,(double lat, double lon)> zipcodes = new Dictionary<int, (double lat, double lon)>()
{{00601,(18.180555,-66.749961)},
{00602,(18.361945,-67.175597)},
{00603,(18.455183,-67.119887)},
{00606,(18.158345,-66.932911)},
{00610,(18.295366,-67.125135)},
{00612,(18.402253,-66.711397)},
{00616,(18.420412,-66.671979)},
{00617,(18.445147,-66.559696)},
{00622,(17.991245,-67.153993)},
{00623,(18.083361,-67.153897)},
{00624,(18.064919,-66.716683)},
{00627,(18.412600,-66.863926)},
{00631,(18.190607,-66.832041)},
... goes on and on...
{99922,(55.307528,-133.046815)},
{99923,(56.002315,-130.041026)},
{99925,(55.550204,-132.945933)},
{99926,(55.138352,-131.470424)},
{99927,(56.239062,-133.457924)},
{99929,(56.370751,-131.693301)}}; // total is about 33100 lines
}
}@jcouv commented on Wed Sep 20 2017
I'm able to repro this. The program compiles fine, but it overflows when run.
The strange thing is that decompiling the static constructor shows that it only expects to use very little IL stack (.maxstack 4 from debug compilation):
.method private hidebysig specialname rtspecialname static
void .cctor() cil managed
{
// Code size 1160053 (0x11b375)
.maxstack 4
.locals init (class [mscorlib]System.Collections.Generic.Dictionary`2<int32,valuetype [mscorlib]System.ValueTuple`2<float64,float64>> V_0)
IL_0000: newobj instance void class [mscorlib]System.Collections.Generic.Dictionary`2<int32,valuetype [mscorlib]System.ValueTuple`2<float64,float64>>::.ctor()
IL_0005: stloc.0
IL_0006: ldloc.0
IL_0007: ldc.i4 0x259
IL_000c: ldc.r8 18.180554999999998
IL_0015: ldc.r8 -66.749960999999999
IL_001e: newobj instance void valuetype [mscorlib]System.ValueTuple`2<float64,float64>::.ctor(!0,
!1)
IL_0023: callvirt instance void class [mscorlib]System.Collections.Generic.Dictionary`2<int32,valuetype [mscorlib]System.ValueTuple`2<float64,float64>>::Add(!0,
!1)
IL_0028: nop
IL_0029: ldloc.0
IL_002a: ldc.i4 0x25a
IL_002f: ldc.r8 18.361944999999999
IL_0038: ldc.r8 -67.175596999999996
IL_0041: newobj instance void valuetype [mscorlib]System.ValueTuple`2<float64,float64>::.ctor(!0,
!1)
IL_0046: callvirt instance void class [mscorlib]System.Collections.Generic.Dictionary`2<int32,valuetype [mscorlib]System.ValueTuple`2<float64,float64>>::Add(!0,
!1)
IL_004b: nop
IL_004c: ldloc.0
IL_004d: ldc.i4 0x25b
IL_0052: ldc.r8 18.455183000000002
IL_005b: ldc.r8 -67.119887000000006
IL_0064: newobj instance void valuetype [mscorlib]System.ValueTuple`2<float64,float64>::.ctor(!0,
!1)
IL_0069: callvirt instance void class [mscorlib]System.Collections.Generic.Dictionary`2<int32,valuetype [mscorlib]System.ValueTuple`2<float64,float64>>::Add(!0,
!1)
IL_006e: nop
IL_006f: ldloc.0
IL_0070: ldc.i4 0x25e
IL_0075: ldc.r8 18.158345000000001
IL_007e: ldc.r8 -66.932911000000004
IL_0087: newobj instance void valuetype [mscorlib]System.ValueTuple`2<float64,float64>::.ctor(!0,
!1)
IL_008c: callvirt instance void class [mscorlib]System.Collections.Generic.Dictionary`2<int32,valuetype [mscorlib]System.ValueTuple`2<float64,float64>>::Add(!0,
!1)
... repeats ...
I've tested this with debug build and also optimized build (/o+ compiler option), but both overflow at runtime.
category:correctness
theme:large-methods
skill-level:expert
cost:medium