Jens Rehsack <rehsack@xxxxxxxxxxxxxx> writes: > 2010/10/12 Ian Lance Taylor <iant@xxxxxxxxxx>: >> Jens Rehsack <rehsack@xxxxxxxxxxxxxx> writes: >> >>> I currently write some c++ code using libConfuse >>> (http://savannah.nongnu.org/projects/confuse/). >>> During initialisation of the required cfg_opt_t structures I get a >>> (very) lot of warnings like: >>> c2.cpp:11: warning: deprecated conversion from string constant to âchar*' >>> >>> I attached a small example to demonstrate the problem. It's not >>> trivial - changing the "name" member >>> of struct demo being const, free failes (and is invalid, because >>> there're demo_opt instances with >>> modifyable names). >>> >>> Any suggestions welcome. >>> 1) Killing the warning with -Wno-... is not an option >>> 2) Remove the finding using const_cast<char *>() is the same as (1) >>> 3) initializing the struct using strdup is neither reasonable >> >> I'm not sure what you want us to suggest. ÂYou say that the names are >> modifiable. > > Where do I say that? I apologize saying this (must be happened because > of my not so good english). "changing the "name" member of struct demo being const, free failes (and is invalid, because there're demo_opt instances with modifyable names)." I apologize if I misread that sentence. >> ÂString constants are not modifiable. ÂIf the strings are >> indeed modified, and you pass in a string constant, then your program is >> going to crash when the library tries to modify the strings. ÂThe gcc >> warning is helpfully pointing that out. > > Correct. And if the strings are not modifiable? (I thought I provided an > example which shows, that they neither are assumed being modifiable > nor being modified). > >> This is not a gcc issue. ÂIt's a C++ language issue. ÂIf you need a >> modifiable string, then you must not use a string constant. > > How can this being expressed without declaring dozen of helper > variables? I am not sure that I understand what you are asking. Can you provide a short, standalone, bit of code showing the problem? Is there any reason to think that this is a gcc issue rather than a C++ issue? Ian
