I'm trying to assemble a simple "Hello world" application with Masm32. It assembles fine but when I try to link it, the linker says
LINK : error LNK2001: unresolved external symbol _WinMainCRTStartup prog1.exe : fatal error LNK1120: 1 unresolved externals
This is the source code of the program:
.586P
.MODEL FLAT, STDCALL
STD_OUTPUT_HANDLE equ -11
; Prototypes of external procedures
EXTERN GetStdHandle@4:NEAR
EXTERN WriteConsoleA@20:NEAR
EXTERN ExitProcess@4:NEAR
; INCLUDELIB directives for the linker
includelib c:\masm32\lib\user32.lib
includelib c:\masm32\lib\kernel32.lib
;============ data segment =================
_DATA SEGMENT
HANDL DWORD ?
BUFER DB "Hello world\n", 0
NUMB DWORD ?
NUMW DWORD ?
_DATA ENDS
_TEXT SEGMENT
MAIN:
;====== Get the output handle ======
PUSH STD_OUTPUT_HANDLE
CALL GetStdHandle@4
MOV HANDL, EAX
; Output the buffer contents to the console
PUSH 0
PUSH OFFSET NUMW
PUSH NUMB
PUSH OFFSET BUFER
PUSH HANDL
CALL WriteConsoleA@20
;Exit application
PUSH 0
CALL ExitProcess@4
_TEXT ENDS
END
I found in some forums that this is caused by the encode type. However it doesn't seem to matter to my problem
The linker assumes the default name for entry point.
You have a few options.
1. Use the C libraries on the platform, which because you're using MASM, I assume you don't want to.
2. Rename your MAIN to _WinMainCRTStartup
3. Use "-entry:MAIN" on the Link.exe command-line (you may need a "public MAIN" line)