Charles,
I'm sorry for taking so long to get back to you on your question about if I could compile 64 bit Windows C applications under Wine using gcc 64 bit.
Good News!
Wine Command Console
C:\TDM-GCC-64\examples>dir
Volume in drive C has no label.
Volume Serial Number is 0000-0000
Directory of C:\TDM-GCC-64\examples
1/16/2014 8:55 PM <DIR> .
1/16/2014 8:55 PM <DIR> ..
1/16/2014 8:55 PM 57 hello.c
1 file 57 bytes
2 directories 151,265,079,296 bytes free
C:\TDM-GCC-64\examples>gcc hello.c -o hello
C:\TDM-GCC-64\examples>./hello
Hello World
C:\TDM-GCC-64\examples>
Linux Terminal
jrs@laptop:~/.wine/drive_c/TDM-GCC-64/examples$ ls -l
total 132
-rw-rw-r-- 1 jrs jrs 57 Jan 16 20:55 hello.c
-rwxrwxr-x 1 jrs jrs 127203 Jan 16 20:56 hello.exe
jrs@laptop:~/.wine/drive_c/TDM-GCC-64/examples$ file hello.exe
hello.exe: PE32+ executable (console) x86-64, for MS Windows
jrs@laptop:~/.wine/drive_c/TDM-GCC-64/examples$
jrs@laptop:~/.wine/drive_c/TDM-GCC-64/examples$ strip -s hello.exe
jrs@laptop:~/.wine/drive_c/TDM-GCC-64/examples$ ls -l
total 20
-rw-rw-r-- 1 jrs jrs 57 Jan 16 20:55 hello.c
-rwxrwxr-x 1 jrs jrs 15872 Jan 16 21:10 hello.exe
jrs@laptop:~/.wine/drive_c/TDM-GCC-64/examples$
Bad News!
I tried to compile your CBasicStringClassLibrary under TDM-CGG-64 and it defaulted to a 32 bit executable. When I forced the -m64 compiler switch, this is the message I got.
C:\c_basic>gcc -m64 Test.c -o Test
Test.c:1:0: sorry, unimplemented: 64-bit mode not compiled in
C:\c_basic>