ldd says library isn't found by compile completes successfully
c++, gcc, makefile
Solution
The library files are shared objects, which means that they will not be resolved until run time. In order for ldd to find them (assuming Linux or other Unix variant) you will need to add the path the libraries to your LD_LIBRARY_PATH (there is another path env that can be used but I can't think of it right now) and then ldd should be able to find the library.
Problem
I am attempting to compile project. It compiles successfully. My `make` command exits with a status code of `0` and there are no errors displayed. However, the project is not working, and when I run `ldd -d <file>` it shows that I have two libraries that are not found. ``` >ldd -d output_file.so linux-gate.so.1 => (0xf77e0000) libvstdlib_srv.so => not found libtier0_srv.so => not found libm.so.6 => /lib/libm.so.6 (0xf7760000) libdl.so.2 => /lib/libdl.so.2 (0xf775b000) libc.so.6 => /lib/libc.so.6 (0xf75a9000) /lib/ld-linux.so.2 (0x46e4a000) undefined symbol: pfVectorNormalize (output_file.so) undefined symbol: _Z12VectorAnglesRK6VectorR6QAngle (output_file.so) undefined symbol: pfSqrt (output_file.so) undefined symbol: __cxa_guard_acquire (output_file.so) undefined symbol: __cxa_guard_release (output_file.so) undefined symbol: _Z6ConMsgPKcz (output_file.so) undefined symbol: Warning (output_file.so) undefined symbol: __dynamic_cast (output_file.so) undefined symbol: _Z11ConColorMsgRK5ColorPKcz (output_file.so) undefined symbol: Error (output_file.so) undefined symbol: AssertValidStringPtr (output_file.so) undefined symbol: _AssertValidWritePtr (output_file.so) undefined symbol: _AssertValidReadPtr (output_file.so) undefined symbol: _ZTVN10__cxxabiv121__vmi_class_type_infoE (output_file.so) undefined symbol: _ZTVN10__cxxabiv120__si_class_type_infoE (output_file.so) undefined symbol: _ZTVN10__cxxabiv117__class_type_infoE (output_file.so) undefined symbol: __gxx_personality_v0 (output_file.so) ``` These two libraries are set up as symbolic links to the actual location of the file: ``` ... lrwxrwxrwx 1 Andy Andy 62 May 2 12:30 libtier0_srv.so -> /home/dev/sdks/hl2sdk-ob-valve/lib/linux/libtier0_srv.so lrwxrwxrwx 1 Andy Andy 64 May 2 12:30 libvstdlib_srv.so -> /home/dev/sdks/hl2sdk-ob-valve/lib/linux/libvstdlib_srv.so -rw-r--r-- 1 Andy Andy 5444 May 2 11:53 Makefile ... ``` The `gcc` command being run is `gcc -I/home/dev/sdks/hl2sdk-ob-valve/public/game/server -I. -I.. -ICEntity -Isdk -I/home/dev/project1/hl2sdk-ob-valve/public -I/home/dev/sdks/hl2sdk-ob-valve/public/engine -I/home/dev/sdks/hl2sdk-ob-valve/public/tier0 -I/home/dev/sdks/hl2sdk-ob-valve/public/tier1 -I/home/dev/sdks/hl2sdk-ob-valve/public/mathlib -I/home/dev/project1/mmsource-central/core -I/home/dev/project1/mmsource-central/core/sourcehook -I/home/dev/project1/sourcemod-central/public -I/home/dev/project1/sourcemod-central/public/sourcepawn -I/home/dev/project1/sourcemod-central/core project1_output/sdk/smsdk_ext.o project1_output/extension.o project1_output/CTrackingProjectile.o project1_output/CSentryRocket.o project1_output/CProjectileRocket.o project1_output/CProjectileArrow.o project1_output/CProjectileFlare.o project1_output/CProjectilePipe.o project1_output/CProjectileSyringe.o project1_output/CEntity/CEntity.o project1_output/CEntity/CEntityManager.o project1_output/CEntity/CPlayer.o /home/dev/project1/hl2sdk-ob-valve/lib/linux/tier1_i486.a libvstdlib_srv.so libtier0_srv.so -m32 -lm -ldl -static-libgcc -shared -o project1_output/output_file.so` My questions are: 1.) Why are those two libraries not found even though they are symlinked? 2.) The undefined symbols are part of the `mathlib` package, which is included in the `gcc` command. `-I/home/dev/sdks/hl2sdk-ob-valve/public/mathlib` Why would these be undefined, despite being included? `c++` is not my language of choice and I know enough about Makefiles to be dangerous, but not really to fix anything, so I apologize if this is not enough information. I can provide more as needed.