* John Calcote wrote on Tue, Jun 24, 2008 at 05:51:05PM CEST: > This bit of code is part of a larger chunk of code that fills in a > Microsoft OS structure for walking the stack: > > #ifdef FLM_64BIT > DWORD64 udDisplacement; > #else > DWORD udDisplacement; > #endif > if (SymGetSymFromAddr(gv_hMemProcess, > *puiStack, &udDisplacement, pImgHlpSymbol)) > ... > > As you can see here, the OS function SymGetSymFromAddr expects to be > passed a 64-bit quantity (DWORD64) on 64-bit platforms, and a 32-bit > quantity (DWORD) on 32-bit platforms. Why didn't they define this > parameter to use an opaque type, like size_t, for instance? Well, even if they don't: unless you use SymGetSymFromAddr exactly once (presumably in a wrapper function), why not do it yourself, and limit the preprocessor magic to one spot: #ifdef FLM_64BIT typedef SymGetSymFromAddrDisp DWORD64; #else typedef SymGetSymFromAddrDisp DWORD; #endif (/me shudders a bit about the naming convention) and use that throughout? > [...] you used the -m32/64 > flag as part of the compiler variable, not the flags variable. This > would not have occurred to me, but it makes complete sense in hind > sight. The -mxx flag changes the compiler in a very fundamental way, so > it's best applied to the $CXX variable. Well, I used to tell people to put it in CFLAGS/CXXFLAGS. That's wrong as then the preprocessor is neglected, should it run on its own anywhere (it most likely will during some configure test). So I started putting it in both CPPFLAGS and LDFLAGS. That's not so bad, in that it fixes all interesting languages at once (except maybe un-preprocessed Fortran) but it does require that these variables are not forgotten anywhere, even in makefiles not written by automake. Adding it to CC/CXX is pretty safe. Cheers, Ralf _______________________________________________ Autoconf mailing list Autoconf@xxxxxxx http://lists.gnu.org/mailman/listinfo/autoconf
