I agree that the description is confusing. Since I just grasped them, I’ll try to summarize: (__bridge_transfer <NSType>) op or alternatively CFBridgingRelease(op) is used to consume a retain-count of a CFTypeRef while transferring it over to ARC. This could also be represented by id someObj = (__bridge <NSType>) op; CFRelease(op); (__bridge_retained <CFType>) op or alternatively … Read more
Xcode 4.2 had finally added support for C++0X: In the project build settings screen, switch on “All” options. In the “Build Options” section, set compiler to “Apple LLVM compiler 3.0”. Scroll down to “Apple LLVM Compiler 3.0 – Language” section and set “C++ Language Dialect” to “C++0X” and “C++ Standard Library” to “libc++”. The std::move(), … Read more
Its in linux/limits.h. #define PATH_MAX 4096 /* # chars in a path name including nul */ #include <linux/limits.h> char current_path[PATH_MAX]; PATH_MAX has some flaws as mentioned in this blog (thanks paulsm4)
The translation of void* is “Dear compiler, this is a pointer, an there is no additional information for you on this.”. Usually the compiler knows better than you (the programmer), because of information he got earlier and still remembers and you might have forgotten about. But in this special case, you know better or need … Read more
I’m curious: What compiler are you using? What’s the value of CMAKE_OSX_SYSROOT? I’m fairly convinced this is the result of a wrong CMAKE_OSX_SYSROOT. I had the problem you’re describing when using python bindings for clang (where CMake doesn’t manage the compiler call), but I managed to recreate the error in CMake by doing: set(CMAKE_OSX_SYSROOT “”) … Read more
You need to rebuild boost using clang++ -stdlib=libc++. libc++ is not binary compatible with gcc’s libstdc++ (except for some low level stuff such as operator new). For example the std::string in gcc’s libstdc++ is refcounted, whereas in libc++ it uses the “short string optimization”. If you were to accidentally mix these two strings in the … Read more
I found this related question. To sum it up, to find out about compiler optimization passes: llvm-as < /dev/null | opt -O3 -disable-output -debug-pass=Arguments As pointed out in Geoff Nixon‘s answer (+1), clang additionally runs some higher level optimizations, which we can retrieve with: echo ‘int;’ | clang -xc -O3 – -o /dev/null -\#\#\# Documentation … Read more
TL;DR clang is correct, this is known gcc bug. You can either use intptr_t instead and cast when you need to use the value or if that is not workable then both gcc and clang support a little documented work-around that should allow your particular use case. Details So clang is correct on this one … Read more
Try using Homebrew’s llvm: brew install llvm You then have all the llvm binaries in /usr/local/opt/llvm/bin. Compile the OpenMP Hello World program. Put omp_hello.c /****************************************************************************** * FILE: omp_hello.c * DESCRIPTION: * OpenMP Example – Hello World – C/C++ Version * In this simple example, the master thread forks a parallel region. * All threads in … Read more