[Devbuilds] echelon.wad crashes on startup

[Xaser]

The recent megawad Echelon crashes on startup. Quick DWF crosspost from here:

Just as a heads up, something about this WAD crashes the newest dev builds of ZDoom and GZDoom. I had to downgrade to 2.8.1 to be able to play it.

In the latest build of ZDoom, the game will hang when trying to load the first map, and in the latest build of GZDoom, the game won't even boot up with this WAD loaded. I suspect the problem here has to do with the startup warnings mentioned above by WildWeasel, hence they're not as innocuous as they seem. I don't know if this is a problem on the engine's end or the WAD, but it's something to keep an eye on.

There's a bunch of "Texture 'x' references itself as patch" warnings in the console that are likely related, so this could be a "fix the wad" scenario, but crashing is no fun (and 2.8.1 exhibits nothing of the sort).

[EDIT] The self-referencing textures are indeed the cause. I repaired them in my copy of the wad and it works fine (albeit with other warnings, but I'll report those to the mapper).

[Edward-san]

Stack trace of the beginning of the loop which would lead to the crash:

---

Code: Select all

#0  FMultiPatchTexture::GetColumn (this=0x60d00004fe50, column=0, spans_out=0x7fffffffc090) at /home/edward-san/zdoom/trunk/src/textures/multipatchtexture.cpp:391
No locals.
#1  0x0000000000f31ab7 in FMultiPatchTexture::GetColumn (this=0x60d00004fe50, column=0, spans_out=0x7fffffffc090) at /home/edward-san/zdoom/trunk/src/textures/multipatchtexture.cpp:393
No locals.
#2  0x00000000005cef89 in FSoftwareRenderer::PrecacheTexture (this=0x6020000365d0, tex=0x60d00004fe50, cache=1) at /home/edward-san/zdoom/trunk/src/r_swrenderer.cpp:87
        spanp = <error reading variable spanp (Cannot access memory at address 0xffffffffffffffc0)>
#3  0x00000000005cf67e in FSoftwareRenderer::Precache (this=0x6020000365d0, texhitlist=0x6220000b7100 "\001", actorhitlist=...) at /home/edward-san/zdoom/trunk/src/r_swrenderer.cpp:145
        i = 4128
        spritelist = 0x618000039880 "\""
        it = <error reading variable it (Cannot access memory at address 0xffffffffffffffc1)>
        pair = <error reading variable pair (Cannot access memory at address 0xffffffffffffff81)>
        cnt = 5382
#4  0x0000000000b90a8a in P_PrecacheLevel () at /home/edward-san/zdoom/trunk/src/p_setup.cpp:3427
        i = -1
        hitlist = 0x6220000b7100 "\001"
        actorhitlist = {Nodes = 0x61300010fd00, LastFree = 0x61300010fdc0, Size = 16, NumUsed = 9}
        cnt = 5382
        actor = 0x0
        iterator = {<FThinkerIterator> = {m_ParentType = 0x61400000e640, m_CurrThinker = 0x0, m_Stat = 32 ' ', m_SearchStats = true, m_SearchingFresh = false}, <No data fields>}
#5  0x0000000000b94307 in P_SetupLevel (lumpname=0x603000573afc "MAP01", position=0) at /home/edward-san/zdoom/trunk/src/p_setup.cpp:4153
        times = {{Sec = 9.7532989457249641e-05}, {Sec = 0.00035955599742010236}, {Sec = 6.4302003011107445e-07}, {Sec = 0.0006937960279174149}, {Sec = 0.0032733349944464862}, {Sec = 0.0001162769622169435}, {Sec = 0.00063025701092556119}, {Sec = 5.9754005633294582e-05}, {Sec = 8.8945962488651276e-05}, {Sec = 0.00044925900874659419}, {Sec = 4.4052954763174057e-05}, {Sec = 1.4139804989099503e-06}, {Sec = 0.00024059100542217493}, {Sec = 4.6185043174773455e-05}, {Sec = 0.0010028459946624935}, {Sec = 1.9502011127769947e-05}, {Sec = 0.00089506397489458323}, {Sec = -421933.21179040999}, {Sec = 0}, {Sec = 0}}
        buildthings = 0x7fffffffc510
        numbuildthings = 1102416563
        i = 8
        buildmap = false
        oldvertextable = 0x0
        RequireGLNodes = true
        map = 0x61100021b140
        reloop = true
        startTime = 0
        endTime = 0
        BuildGLNodes = false
        __PRETTY_FUNCTION__ = "void P_SetupLevel(const char*, int)"
#6  0x00000000008f0189 in G_DoLoadLevel (position=0, autosave=false) at /home/edward-san/zdoom/trunk/src/g_level.cpp:1007
        lastposition = 0
        oldgs = GS_STARTUP
        i = 8
        mapname = {Chars = 0x603000573acc "map01", static NullString = {Len = 0, AllocLen = 2, RefCount = 11203, Nothing = "\000"}}
#7  0x00000000008ed92e in G_InitNew (mapname=0x60d00002f3ec "MAP01", bTitleLevel=false) at /home/edward-san/zdoom/trunk/src/g_level.cpp:542
        wantFast = false
        i = 8

[_mental_]

As the given crash is caused by asset management error, I suppose that it's enough to just skip erroneous multipatch texture entries to avoid infinite recursion. Here is a pull request.

[Graf Zahl]

Yes, that continue was indeed missing there.