Here my results after ultra clean compile with GCC on XP 32-bit:

SVN r10046

make all TARGET=mess

Compilation (all tools included) ok, messui.exe was not builded.

Quote:
C:\Emulator\Mess\SVN\Bin\mess>make all TARGET=mess
Linking mess.exe...
Linking ledutil.exe...
Linking imgtool.exe...
Linking castool.exe...
Linking messtest.exe...
Linking dat2html.exe...
Linking wimgtool.exe...
Linking romcmp.exe...
Linking chdman.exe...
Linking jedutil.exe...
Linking unidasm.exe...
Linking ldresample.exe...
Linking ldverify.exe...
Linking regrep.exe...
Linking srcclean.exe...
Linking src2html.exe...
Linking split.exe...


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make all TARGET=mess OSD=winui

Compilation error:

Quote:
C:\Emulator\Mess\SVN\Bin\mess>make all TARGET=mess OSD=winui
Linking mess.exe...
Linking messui.exe...
Linking ledutil.exe...
Linking imgtool.exe...
c:/mingw/bin/../lib/gcc/i686-w64-mingw32/4.4.3/../../../../i686-w64-mingw32/lib/
libmingw32.a(lib32_libmingw32_a-crt0_c.o): In function `main':
/W64_155431-src/build-crt/../mingw-w64-crt/crt/crt0_c.c:18: undefined reference
to `WinMain@16'
collect2: ld returned 1 exit status
make: *** [imgtool.exe] Error 1


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make TARGET=mess

Compilation ok. Only mess.exe was builded.

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make TARGET=mess OSD=winui

Compilation ok. Only messui.exe was builded.

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make TARGET=mess tools

Compilation ok.