On 9/10/2013 7:13 AM, Hartmut Kaiser wrote:

...

The code:

// test_macros_o.cpp

#define f(a) f(x + (a)) #define x 2 #define g f #define h g(~

int main() {

#pragma wave trace(enable)

h 5);

#pragma wave trace(disable)

return 0; }

In the latest C++ standard at 16.3.5 paragraph 5 the expansion of 'h 5)' is given as:

f(2 * (~5))

but the wave.exe driver gives:

C:\Programming\VersionControl\boost\libs\vmd\test\test_macros_o.cpp:11:3: h

C:\Programming\VersionControl\boost\libs\vmd\test\test_macros_o.cpp:4:9: see macro definition: h [ g(~ rescanning [

C:\Programming\VersionControl\boost\libs\vmd\test\test_macros_o.cpp:3:9: see macro definition: g [ f rescanning [ f ] ]

It actually should say something like:

t.cpp:13:4: error: improperly terminated macro invocation or replacement- list terminates in partial macro expansion (not supported yet): missing ')'

You are correct. It does say this on stderr. Sorry for the noise.

This is a known bug in wave caused by its recursive expansion algorithm which does not allow to handle this pathologic corner case. All I could do was to detect and report this.

It might be worth it to fix this known bug.