On 28/10/12 14:12, Ulf Magnusson wrote: > Hi, > > When not using whole program or link-time optimization, the body of a > function must be available to the compiler for it to be able to inline > calls the function when compiling a TU. Hence, you might want to put a > function that is used in multiple TUs in a header file to give the > compiler the opportunity to inline it. However, this forces you to > make the function inline, as multiple definitions of non-inline > functions is not allowed. It seems inline might be used for two > different purposes here: > > (1) To make the function body available to the compiler to give it the > opportunity to inline. > (2) To give the compiler a hint to inline the function. > > But what if you trust the compiler to make the right decision for the > function and don't want to influence the inlining heuristics? I.e., > what if you only want (1) and not (2)? > > Which brings me to my questions: > > - How does making a function inline influence GCC's inlining > heuristics for C++? > - If it does influence the inlining heuristics in some significant > way, then is there some way to get (1) without (2) being forced upon > you? > > (Oh, and please point out if I lied anywhere. :) > > Cheers, > Ulf I guess you may place the function in the common section so that both instances can get coalesced. Still, that's not something I'd encourage you to do.
