gcc compile error ld cannot find -l Permission denied - gcc

Question

When I execute:
gcc D:\project\c\test\collection -Wall -o test main.c -lfoo
it reports the error:
D:\project\c\test\collection>gcc D:\project\c\test\collection -Wall -o test main.c -lfoo
d:/gcc-9.2.0-no-debug/bin/../lib/gcc/x86_64-w64-mingw32/9.2.0/../../../../x86_64-w64-mingw32/bin/ld.exe:
cannot find D:\project\c\test\collection: Permission denied
d:/gcc-9.2.0-no-debug/bin/../lib/gcc/x86_64-w64-mingw32/9.2.0/../../../../x86_64-w64-mingw32/bin/ld.exe:
cannot find -lfoo
collect2.exe: error: ld returned 1 exit status
I followed the steps found here: gcc example
My OS is Windows 10 and I use cmd with administrator role.
UPDATE 1
I execute:
gcc -L D:\project\c\test\collection -Wall -o test main.c -lfoo
and get the error:
gcc -L D:\project\c\test\collection -Wall -o test main.c -lfoo
d:/gcc-9.2.0-no-debug/bin/../lib/gcc/x86_64-w64-mingw32/9.2.0/../../../../x86_64-w64-mingw32/bin/ld.exe: cannot find -lfoo
collect2.exe: error: ld returned 1 exit status
My collection directory has libfoo.so file:
2019/12/28 11:19 <DIR> .
2019/12/28 11:19 <DIR> ..
2019/12/28 10:55 3,262 a.exe
2019/12/28 10:38 87 foo.c
2019/12/28 10:37 80 foo.h
2019/12/28 10:38 838 foo.o
2019/12/28 10:38 47,372 libfoo.so
2019/12/28 10:38 134 main.c
UPDATE 2
I change to execute:
gcc -L / -Wall -o test main.c
and get the error:
//libfoo.dll.a: Unrecognized file: File truncated,collect2.exe: error: ld returned 1 exit status

Answer 1

gcc D:\project\c\test\collection -Wall -o test main.c -lfoo
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Files that aren't part of an option (like -o test or -lfoo) are generally considered to be input files for compiling or linking.
There's a good chance that's meant to be a library location for locating the foo library, simply because the tutorial you're following has almost the exact same line:
gcc -L/home/username/foo -Wall -o test main.c -lfoo
If that's the case, then you're missing the -L to tell it this should be added to the library search path, so something like this should fix it:
gcc -L D:\project\c\test\collection -Wall -o test main.c -lfoo
In any case, since you appear to have all your files in a single directory (source, libs, etc), you don't need to adjust the search path. Or, if you do, you can just used -L. to specify the current directory, something like:
gcc -Wall -o test main.c -L. -lfoo