So 'we' know it's an established scenario of a register being occupied in the x86. The code block asm(" pushl %%ebx cpuid popl %%ebx " : : : "eax", "ecx", "edx"); patched into test_x86_emulator.c just gives a long line of what appear to be syntax style errors and after some legitimate attempts it continues to cough up more of the same style error(s). Here's the actual line compiling the file. gcc -Wstrict-prototypes -O2 -fomit-frame-pointer -fno-strict-aliasing -Wdeclaration-after-statement -I/var/tmp/portage-btrfs/portage/app-emulation/xen-tools-4.3.0-r3/work/xen-4.3.0/tools/tests/x86_emulator/../../../tools/include -c -o test_x86_emulator.o test_x86_emulator.c which yields test_x86_emulator.c: In function cpuid: test_x86_emulator.c:65:5: error: inconsistent operand constraints in an asm make[4]: *** [test_x86_emulator.o] Error 1 Patched, it yields test_x86_emulator.c: In function ‘cpuid’: test_x86_emulator.c:65:9: warning: missing terminating " character [enabled by default] asm(" ^ test_x86_emulator.c:65:5: error: missing terminating " character asm(" ^ test_x86_emulator.c:66:9: error: expected string literal before ‘pushl’ pushl %%ebx ^ test_x86_emulator.c:69:9: error: stray ‘\’ in program " : : : "eax", "ecx", "edx");+ asm ("" "pushl %%ebx\n" ^ test_x86_emulator.c:69:65: warning: missing terminating " character [enabled by default] " : : : "eax", "ecx", "edx");+ asm ("" "pushl %%ebx\n" ^ test_x86_emulator.c:69:9: error: missing terminating " character " : : : "eax", "ecx", "edx");+ asm ("" "pushl %%ebx\n" ^ make[4]: *** [test_x86_emulator.o] Error 1 which makes the line of 'Im still not satisfied ya still got the wrong syntax' errors begin its unwelcome march. Another legitimate attempt to help by another lead to trying Before: asm(" pushl %%ebx cpuid popl %%ebx " : : : "eax", "ecx", "edx"); After: asm("" "pushl %%ebx\n" "cpuid\n" "popl %%ebx\n" : : : "eax", "ecx", "edx"); nm about pasting its version of error, after all it's just error. What I did do was to go to the source and run indent and tried that resultant syntax and the list grew. What 2 of us did was to run the initial code block locally in a foo.c and sure it compiled. Put it in the xensource and run make in the folder where it, the test_x86_emulator.c, resides, and it 'explodes', and the list grew. I came, I tried, I didn't conquer. Please make gcc and its finicky syntax wants do what we couldn't, and i can commit the patch being the xen maintainer.
fixed this by drop compiling tools/tests
