Linux (Arch Linux) x86_64 - Segfault when launching game

[V0rt3x667]

Hi, I can compile and run version v1.09.540 with no issues, however when compiling either v1.10.000 or the current master branch I get a segfault error when running the executable. I am using an old Dell Latitude with Intel graphics so I am enquiring if the requirements for OpenGL or Vulkan (If used) have changed?

The commands I use to compile theforceengine are:

cmake . \ -B"build" \ -G"Ninja" \ -DCMAKE_BUILD_RPATH_USE_ORIGIN="ON" \ -DCMAKE_BUILD_TYPE="Release" \ -DCMAKE_C_COMPILER="clang" \ -DCMAKE_CXX_COMPILER="clang++" \ -DCMAKE_EXE_LINKER_FLAGS_INIT="-fuse-ld=lld" \ -DCMAKE_INSTALL_PREFIX="/opt/archypie/ports/forceengine" \ -DCMAKE_MODULE_LINKER_FLAGS_INIT="-fuse-ld=lld" \ -DCMAKE_SHARED_LINKER_FLAGS_INIT="-fuse-ld=lld" \ -Wno-dev ninja -C build

If no hardware requirements have changed please let me know and I will provide a backtrace. Thanks

[luciusDXL]

There should be no change in hardware requirements. Though its possible that I added extra checks somewhere, but that shouldn't cause a crash. Do you have a GPU capable of at least OpenGL 3.3 features? Can you show your log file (the_force_engine_log.txt)?

[mlauss2]

Try building with gnu ld please, i.e. drop all that "-fuse-ld=lld" stuff.

EDIT: I can't even build it with lld, just gnu ld and mold. (i just added "-fuse-ld=mold" to the cxxflags). What did you do to get lld to link the final binary? EDIT2: If you have a new enough CMake (3.29+), you could simply add "-DCMAKE_LINKER_TYPE=LLD" and drop all that "-fuse-ld=lld" stuff altogether. Still can't link it with lld though, it wants a ".lib" file for SDL2

[V0rt3x667]

You have to sed the following to build with lld: sed "s|#pragma comment(lib, \"SDL2main.lib\")|//#pragma comment(lib, \"SDL2main.lib\")|g" -i "./TheForceEngine/main.cpp"

I previously tested with mold. I can try again with GCC & LD and get back to you.

[V0rt3x667]

v1.10.000 builds and runs fine with gcc/ld but not with clang/ld or clang/lld. I have attached the logfile for the clang/ld build. Thanks for your help.

the_force_engine_log.txt

[mlauss2]

Ah, thanks for the hint, indeed this line should be moved under a "#ifdef _WIN32" clause.

I was now able to build TFE with clang-18.1.8 and lld-18.1.8 and from a quick test it runs just fine. After your build finishes, does it start if you run "build/theforceengine" ?

Can you please do an "addr2line -e /path/to/theforceengine.exe 0x5d7604992fad" (i.e. address 003 of the crashlog, where the real crash happens), or run it under gdb and get a backtrace please? Although, if you say it runs when built with gcc/ld, your system might just have a bad clang/lld combo.

Thanks!

[V0rt3x667]

I built theforceengine with the Debug flag set. I hope the back trace below is sufficient, it is for the clang/lld combo. I tried the addr2line option but it just returned ??:0

[Main] The Force Engine v1.10.000+                                                                                                                    

Program received signal SIGSEGV, Segmentation fault.
Downloading source file /usr/src/debug/glibc/glibc/string/../sysdeps/x86_64/multiarch/strlen-sse2.S
__strlen_sse2 () at ../sysdeps/x86_64/multiarch/strlen-sse2.S:142                                                                                     
142     movdqu  (%rax), %xmm4
(gdb) bt
#0  __strlen_sse2 () at ../sysdeps/x86_64/multiarch/strlen-sse2.S:142
#1  0x000055555568d4fe in FileUtil::findFileObjectNoCase (filename=0x4000000000 <error: Cannot access memory at address 0x4000000000>, objisdir=true)
    at /home/aaron/GitHub/ArchyPie-Setup/tmp/build/forceengine/TheForceEngine/TFE_FileSystem/fileutil-posix.cpp:266
#2  0x000055555568d491 in FileUtil::directoryExits (path=0x4000000000 <error: Cannot access memory at address 0x4000000000>, 
    outPath=outPath@entry=0x0) at /home/aaron/GitHub/ArchyPie-Setup/tmp/build/forceengine/TheForceEngine/TFE_FileSystem/fileutil-posix.cpp:231
#3  0x000055555574268c in TFE_Settings::autodetectGamePaths ()
    at /home/aaron/GitHub/ArchyPie-Setup/tmp/build/forceengine/TheForceEngine/TFE_Settings/settings.cpp:232
#4  0x00005555557423e4 in TFE_Settings::readFromDisk ()
    at /home/aaron/GitHub/ArchyPie-Setup/tmp/build/forceengine/TheForceEngine/TFE_Settings/settings.cpp:256
#5  0x00005555557422dd in TFE_Settings::init (firstRun=@0x7fffffffdc5f: false)
    at /home/aaron/GitHub/ArchyPie-Setup/tmp/build/forceengine/TheForceEngine/TFE_Settings/settings.cpp:124
#6  0x00005555557b8a4d in main (argc=1, argv=0x7fffffffe798) at /home/aaron/GitHub/ArchyPie-Setup/tmp/build/forceengine/TheForceEngine/main.cpp:568 

[mlauss2]

Please apply this patch and rebuild:

index 9724175e..d5a7db01 100644
--- a/TheForceEngine/TFE_Settings/settings.cpp
+++ b/TheForceEngine/TFE_Settings/settings.cpp
@@ -227,6 +227,7 @@ namespace TFE_Settings
                                }
                        }
 #endif
+#ifdef _WIN32
                        // If the registry approach fails, just try looking in the various hardcoded paths.
                        if (!pathValid)
                        {
@@ -242,6 +243,7 @@ namespace TFE_Settings
                                        }
                                }
                        }
+#endif
                }
                writeToDisk();
        }

[V0rt3x667]

Hi, the patch fixes the issue. Thanks.

[mlauss2]

From my POV the "issue" is in your toolchain. Your lld does stupid things with perfectly fine string constants that happen to be windows paths. I cannot reproduce it though with my vanilla lld/clang setup, I'm inclined to believe that this is either system- or distro specific. But it's not a TFE problem.

[V0rt3x667]

v1.09.540 builds and runs just fine with the same tool chain. Its fine if you do not wish to pursue the issue further as the patch you provided works. I doubt many will be using the latest versions of clang & lld anyway. It works fine with gcc & ld as is so if you want to close the issue that is fine. Thanks for your help on this.

[mlauss2]

if your gnu ld and mold work, only lld does not, while I cannot reproduce this at all, I see no reason to pursue this any further to work around a single broken lld linker.

It looks like your lld misplaces the windows path names array ("c_darkForcesLocations[]" in TheForceEngine/TFE_Settings/gameSettingsData.h) or computes the wrong location since the address of the path passed to the crashing function seems way off (the 0x004000000000), it should point to the start of a constant string pool in memory. This was probably exposed by the additional strings added to TFE since the last release.

[mlauss2]

I'm curious, does this change anything?

index bdcde75b..003fc717 100644
--- a/TheForceEngine/TFE_Settings/gameSourceData.h
+++ b/TheForceEngine/TFE_Settings/gameSourceData.h
@@ -71,7 +71,7 @@ namespace TFE_Settings
                "OUTLAWS.LAB",                  // Game_Outlaws
        };

-       static const char* c_darkForcesLocations[] =
+       static const char* const c_darkForcesLocations[] =
        {
                // C drive
                "C:/Program Files (x86)/Steam/steamapps/common/dark forces/Game/",
@@ -88,7 +88,7 @@ namespace TFE_Settings
                "D:/Program Files (x86)/GOG.com/Star Wars - Dark Forces/",
                "D:/GOG Games/Star Wars - Dark Forces/",
        };
-       static const char* c_outlawsLocations[] =
+       static const char* const c_outlawsLocations[] =
        {
                // C drive
                "C:/Program Files (x86)/Steam/steamapps/common/outlaws/",
@@ -103,7 +103,7 @@ namespace TFE_Settings
        };
        static const u32 c_hardcodedPathCount = TFE_ARRAYSIZE(c_darkForcesLocations);

-       static const char** c_gameLocations[] =
+       static const char* const * c_gameLocations[] =
        {
                c_darkForcesLocations,
                c_outlawsLocations
diff --git a/TheForceEngine/TFE_Settings/settings.cpp b/TheForceEngine/TFE_Settings/settings.cpp
index 9724175e..43b5cfac 100644
--- a/TheForceEngine/TFE_Settings/settings.cpp
+++ b/TheForceEngine/TFE_Settings/settings.cpp
@@ -231,7 +231,7 @@ namespace TFE_Settings
                        if (!pathValid)
                        {
                                // Try various possible locations.
-                               const char** locations = c_gameLocations[gameId];
+                               const char* const * locations = c_gameLocations[gameId];
                                for (u32 i = 0; i < c_hardcodedPathCount; i++)
                                {
                                        if (FileUtil::directoryExits(locations[i]))

[V0rt3x667]

Hi, applying the patch above in addition to the previous one has not broken anything and work just fine. Thanks.

[mlauss2]

Please test this new patch alone (without the other).

[V0rt3x667]

I have tested the patch by itself and it works fine.

[mlauss2]

Interesting. We can add that to the TFE codebase, but I still prefer your lld getting fixed :) I'll add this to my "pile of little fixes PR". Thanks for testing!

[V0rt3x667]

Thanks again for your help.