Thread: Linkage issue/s

So I finally fixed a bunch of includes that needed to be changed as a result of reorganisation and a number of code faults generated as a result of an API change, got everything to compile without issue only to find and the last stretch the linker can't connect the dots, someone tell me what I'm doing wrong here:

Code:

INC_PATHS=../include
IS_WINDOWS:=$(if $(Program Files),1,)
IS_WIN64:=$(if ${Program Files(x86)},1,)
IS_WIN32:=$(if $(IS_WIN64),,$(IS_WINDOWS))
EXE?=$(if $(IS_WINDOWS),exe,AppImage)
IFLAGS:=$(INC_PATHS:%=-I %)
CFLAGS:=-Wall $(IFLAGS)

mcc: libmcc_core.so
test: test.$(EXE)

libmcc_core.so: $(wildcard mcc/core/*.o)
	gcc -lpthread -o $@ $^

test.AppImage: test/unit_tests.o libmcc_core.so
	gcc -o $@ $^

mcc/core/vflt.c: mcc/core/vflt.h
mcc/core/vint.c: mcc/core/vint.h
mcc/core/get.c: mcc/core/get.h
mcc/core/mem.c: mcc/core/mem.h
mcc/core/vflt.h: mcc/core/vint.h
mcc/core/vint.h: mcc/core/get.h
mcc/core/get.h: mcc/core/mem.h
mcc/core/mem.h: mcc/malloc.h
mcc/malloc.h: mcc/vmalloc.h
mcc/vmalloc.h: mcc/inttypes.h
mcc/inttypes.h: mcc/stdint.h
mcc/stdint.h: mcc/limits.h
mcc/limits.h: mcc/core/sys.h
mcc/core/sys.h:
test/unit_tests.o: test/unit_tests.c
test/unit_tests.c: test/core/vint.c

%.o: %.c
	clang $(CFLAGS) -o $@ -c $<

force: ;

Output from my attempt:

Code:

...
make[2]: Entering directory '~/mitsy/src'
clang -Wall -I ../include -o test/unit_tests.o -c test/unit_tests.c
gcc -lpthread -o libmcc_core.so mcc/core/vint.o mcc/core/vflt.o mcc/core/get.o mcc/core/mem.o
gcc -o test.AppImage test/unit_tests.o libmcc_core.so
/usr/bin/ld: test/unit_tests.o: in function `test__vint':
unit_tests.c:(.text+0x487): undefined reference to `mcc_vint_wrap'
/usr/bin/ld: unit_tests.c:(.text+0x4af): undefined reference to `mcc_vint_size_and_fill'
/usr/bin/ld: unit_tests.c:(.text+0x4e2): undefined reference to `mcc_vint_wrap'
/usr/bin/ld: unit_tests.c:(.text+0x513): undefined reference to `mcc_vint_size_and_fill'
/usr/bin/ld: unit_tests.c:(.text+0x546): undefined reference to `mcc_vint_wrap'
/usr/bin/ld: unit_tests.c:(.text+0x577): undefined reference to `mcc_vint_size_and_fill'
/usr/bin/ld: unit_tests.c:(.text+0x5f3): undefined reference to `mcc__vint_op_not'
/usr/bin/ld: unit_tests.c:(.text+0x65b): undefined reference to `mcc__vint_op_aor'
/usr/bin/ld: unit_tests.c:(.text+0x6c3): undefined reference to `mcc__vint_op_xor'
/usr/bin/ld: unit_tests.c:(.text+0x72b): undefined reference to `mcc__vint_op_and'
/usr/bin/ld: unit_tests.c:(.text+0x77b): undefined reference to `mcc__vint_op_inc'
/usr/bin/ld: unit_tests.c:(.text+0x7e3): undefined reference to `mcc__vint_op_add'
/usr/bin/ld: unit_tests.c:(.text+0x84c): undefined reference to `mcc__vint_op_mul'
/usr/bin/ld: unit_tests.c:(.text+0x89c): undefined reference to `mcc__vint_op_dec'
/usr/bin/ld: unit_tests.c:(.text+0x905): undefined reference to `mcc__vint_op_sub'
/usr/bin/ld: unit_tests.c:(.text+0x9df): undefined reference to `mcc___vint_op_div'
/usr/bin/ld: unit_tests.c:(.text+0xa95): undefined reference to `mcc___vint_op_div'
/usr/bin/ld: unit_tests.c:(.text+0xb52): undefined reference to `mcc__vint_op_cmp'
/usr/bin/ld: unit_tests.c:(.text+0xb9d): undefined reference to `mcc_vint_to_val'
/usr/bin/ld: unit_tests.c:(.text+0xc22): undefined reference to `mcc__vint_op_cmp'
/usr/bin/ld: unit_tests.c:(.text+0xc6d): undefined reference to `mcc_vint_to_val'
/usr/bin/ld: unit_tests.c:(.text+0xcf1): undefined reference to `mcc__vint_op_cmp'
/usr/bin/ld: unit_tests.c:(.text+0xd3c): undefined reference to `mcc_vint_to_val'
/usr/bin/ld: unit_tests.c:(.text+0xdd6): undefined reference to `mcc__vint_op_shr'
/usr/bin/ld: unit_tests.c:(.text+0xe5a): undefined reference to `mcc__vint_op_cmp'
/usr/bin/ld: unit_tests.c:(.text+0xea5): undefined reference to `mcc_vint_to_val'
/usr/bin/ld: unit_tests.c:(.text+0xf15): undefined reference to `mcc__vint_op_cmp'
make[2]: Leaving directory '~/mitsy/src'
make[1]: Leaving directory '~/mitsy/src/test'
/usr/bin/ld: unit_tests.c:(.text+0xf60): undefined reference to `mcc_vint_to_val'
/usr/bin/ld: unit_tests.c:(.text+0xfe2): undefined reference to `mcc__vint_op_shl'
/usr/bin/ld: unit_tests.c:(.text+0x1066): undefined reference to `mcc__vint_op_cmp'
/usr/bin/ld: unit_tests.c:(.text+0x10b1): undefined reference to `mcc_vint_to_val'
/usr/bin/ld: unit_tests.c:(.text+0x1121): undefined reference to `mcc__vint_op_cmp'
/usr/bin/ld: unit_tests.c:(.text+0x116c): undefined reference to `mcc_vint_to_val'
/usr/bin/ld: unit_tests.c:(.text+0x1218): undefined reference to `mcc_vint_size'
/usr/bin/ld: unit_tests.c:(.text+0x1231): undefined reference to `mcc_vint_size'
/usr/bin/ld: unit_tests.c:(.text+0x124a): undefined reference to `mcc_vint_size'
collect2: error: ld returned 1 exit status
make[2]: *** [makefile:16: test.AppImage] Error 1
make[1]: *** [makefile:2: makefile] Error 2
make: *** [makefile:2: makefile] Error 2
Compilation failed.

Originally Posted by Salem

> libmcc_core.so: $(wildcard mcc/core/*.o)
> gcc -lpthread -o $@ $^
I doubt this is creating a valid .so file.

Did work because I had the objects but now swapped for this:

Code:

mcc_core_sources:=$(wildcard mcc/core/*.c)
mcc_core_objects:=$(mcc_core_sources:%.c=%.o)
mcc_test_sources:=test/unit_tests.c
mcc_test_objects:=$(test_core_sources:%.c=%.o)

Originally Posted by Salem

Try using the 'file' utility.

Code:

$ file /usr/lib/openmpi/lib/libmpi.so.12.0.2 
/usr/lib/openmpi/lib/libmpi.so.12.0.2: ELF 64-bit LSB shared object, x86-64, version 1 (SYSV), dynamically linked, BuildID[sha1]=cb7d48202b372be192a2ca3d3fcb534410182b75, stripped
$ file a.out
a.out: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/l, for GNU/Linux 2.6.32, BuildID[sha1]=58cb7d060501f3fb1f8a2d0434fcf151e7ec6ea1, not stripped

Didn't bother since what you mentioned below fixed it

Originally Posted by Salem

>test.AppImage: test/unit_tests.o libmcc_core.so
> gcc -o $@ $^
Similarly, you don't just name the library, you need the -l syntax to refer to it.

Now just getting this:

Code:

make test (in directory: ~/mitsy/src)
gcc -lpthread -o libmcc_core.so
/usr/bin/ld: /usr/lib/gcc/x86_64-pc-linux-gnu/9.2.0/../../../../lib/Scrt1.o: in function `_start':
(.text+0x24): undefined reference to `main'
collect2: error: ld returned 1 exit status
make: *** [makefile:17: libmcc_core.so] Error 1
Which is strange since unit_test.c consists of just this right now:

	
Code:
	
#include <mcc/core/tsc.h>
#include <mcc/core/get.h>
#include <mcc/core/base62.h>
#include "core/vint.c"
int main() {
	int ret = test_vint();
	return ( ret == EXIT_SUCCESS ) ? EXIT_SUCCESS : EXIT_FAILURE;
}
Compilation failed.

Okay after some fiddling I realised the objects weren't being created/updated as I originally thought so I resolved that and got as far as this:

Code:

make test (in directory: ~/mitsy/src)
clang -Wall -fPIC -I ../include -o test/unit_tests.o -c test/unit_tests.c
clang -Wall -fPIC -I ../include -o mcc/core/mem.o -c mcc/core/mem.c
clang -Wall -fPIC -I ../include -o mcc/core/vint.o -c mcc/core/vint.c
clang -Wall -fPIC -I ../include -o mcc/core/base62.o -c mcc/core/base62.c
clang -Wall -fPIC -I ../include -o mcc/core/vflt.o -c mcc/core/vflt.c
clang -Wall -fPIC -I ../include -o mcc/core/tsc.o -c mcc/core/tsc.c
clang -Wall -fPIC -I ../include -o mcc/core/get.o -c mcc/core/get.c
gcc -shared -fPIC -L ../lib -lpthread -o ../lib/libmcc_core.so mcc/core/mem.o mcc/core/vint.o mcc/core/base62.o mcc/core/vflt.o mcc/core/tsc.o mcc/core/get.o
gcc -fPIC -L ../lib -lmcc_core -o mcc_unit_test.AppImage test/unit_tests.o
./mcc_unit_test.AppImage
make: execvp: ./mcc_unit_test.AppImage: Permission denied
make: *** [makefile:22: test] Error 127
Compilation failed.

Anyone familiar with linux and forcing auto-mounted drives under current user ownership? I put my files on a fat32 drive cause I got tired of resetting ownership every time I had to reinstall my system when that poxy nvidia driver decided to black screen me at boot, I'm not linux savy enough to fix issues in purely the command interface so I just reinstall after running my live usb and backing up my data. I wouldn't mind using btrfs since reactos has a working driver for that which will no doubt get included in windows sooner or later (which is useful for compiling same code on windows to test mitsy there too) but I don't know how to make the contents publicly accessible to any user on any system I plug into.
The most I know is "chmod -R 777 ./"

Okay with my permission issues resolved I tried linkage again and it worked, the new problem now is when I try to run the app it can't find the library, here's my output:

Code:

make test (in directory: ~/mitsy/src)
clang -Wall -fPIC -I ../include -o test/unit_tests.o -c test/unit_tests.c
clang -Wall -fPIC -I ../include -o mcc/core/mem.o -c mcc/core/mem.c
clang -Wall -fPIC -I ../include -o mcc/core/vint.o -c mcc/core/vint.c
clang -Wall -fPIC -I ../include -o mcc/core/base62.o -c mcc/core/base62.c
clang -Wall -fPIC -I ../include -o mcc/core/vflt.o -c mcc/core/vflt.c
clang -Wall -fPIC -I ../include -o mcc/core/tsc.o -c mcc/core/tsc.c
clang -Wall -fPIC -I ../include -o mcc/core/get.o -c mcc/core/get.c
clang -shared -fPIC -L ../lib -lpthread -o ../lib/libmcc_core.so mcc/core/mem.o mcc/core/vint.o mcc/core/base62.o mcc/core/vflt.o mcc/core/tsc.o mcc/core/get.o
clang -shared -fPIC -L ../lib -lpthread -o libmcc_core.so mcc/core/mem.o mcc/core/vint.o mcc/core/base62.o mcc/core/vflt.o mcc/core/tsc.o mcc/core/get.o
clang -fPIC -L ../lib -lmcc_core -o mcc_unit_test.AppImage test/unit_tests.o
./mcc_unit_test.AppImage
./mcc_unit_test.AppImage: error while loading shared libraries: libmcc_core.so: cannot open shared object file: No such file or directory
make: *** [makefile:24: test] Error 127
Compilation failed.

Originally Posted by awsdert

Weird how setting umask to 777 removed my permissions but clearing it gives me all the permissions I want

It's not weird at all. That's how umask works. From umask(2) - Linux manual page:

Specifically, permissions in the umask are turned off from the mode argument to open(2) and mkdir(2).

Originally Posted by christop

It's not weird at all. That's how umask works. From umask(2) - Linux manual page:

Ah that'll be why then, I just assumed that it would follow a normal user's common sense and set the permissions to the value given

Any ways I finally fixed my linkage issues, the page salem linked wasn't clear enough in WHERE to use -Wl,-rpath or whether to stick a space in after the linker option or another comma, for anyone stuggling with the same problem here's the 3 key points you'll be looking for an example of:

Code:

$(mcc_core_lib): $(mcc_core_objects)
	$(CC) -shared $(BFLAGS) -lpthread -o $@ $^

$(mcc_test_app): $(mcc_test_objects) $(mcc_core_lib)
	$(CC) $(BFLAGS) -lmcc_core -o $@ $(mcc_test_objects) -Wl,-rpath,$(LIB_PATHS)
	
%.o: %.c
	$(CC) $(CFLAGS) -o $@ -c $<