clang

问题 When building with Scons, I can configure it to use clang like so: env["CXX"] = "clang++" However, it doesn't seem to preserve the color information that clang outputs. How can I make scons preserve the color? 回答1: According to the clang documentation, color is enabled only when a color-capable terminal is detected . SCons doesn't automatically pass on all environment variables to the process that runs the compiler, you have pass them explicitly. And TERM is not passed on to clang. Add the

问题 I accidentally found that the Clang compiler allows : inline class AAA { }; in C++. What's this? PS. I reported this to Clang mailing list cfe-dev@cs.uiuc.edu , and now waiting for reply. I'll update this question by I'm informed. 回答1: It's allowed in case you wish to declare a function that returns an object of that class directly after the class' declaration, for example : #include <iostream> inline class AAA { public: AAA() { // Nothing } AAA(const AAA& _Param) { std::cout << "Calling Copy

问题 I saw a snippet of code on CodeGolf that's intended as a compiler bomb, where main is declared as a huge array. I tried the following (non-bomb) version: int main[1] = { 0 }; It seems to compile fine under Clang and with only a warning under GCC: warning: 'main' is usually a function [-Wmain] The resulting binary is, of course, garbage. But why does it compile at all? Is it even allowed by the C specification? The section that I think is relevant says: 5.1.2.2.1 Program startup The function

问题 I've compiled and linked ios app that uses lib (libclang) that uses stat() with no errors. But i'm having runtime error: 2014-07-07 16:55:14.138 LibClangUsage7Demo[74938:60b] started Detected an attempt to call a symbol in system libraries that is not present on the iPhone: stat$INODE64 called from function _ZN4llvm3sys2fs6statusERKNS_5TwineERNS1_11file_statusE in image LibClangUsage7Demo. LLVM code which raises error is (/Unix/Path.inc): error_code status(const Twine &Path, file_status

问题 I was trying to compile some code that uses Boost (1.49), with Clang(& libc++) from trunk. The problematic code boils down to the following: #include <memory> #include <boost/signals2.hpp> int main() { std::shared_ptr<int> s; } When compiled with Clang, the following message is emmited: $ clang++ -I/home/alexander/usr/local/include --stdlib=libc++ -std=c++0x signals2-bug.cpp -o signals2-bug signals2-bug.cpp:6:26: error: implicit instantiation of undefined template 'std::shared_ptr<int>' std:

问题 There is already a question asking about the "real-world" behavior of delete ing a pointer to a base class that lacks a virtual destructor, but the question is restricted to a very limited case (the derived class has no members with non-trivial destructors), and the accepted answer just says there's no way to know without checking the behavior of every compiler. ....but that isn't actually very helpful; knowing that every compiler might behave differently doesn't tell us anything about the

问题 The code below compiles fine with G++ 4.7.2: #include <tuple> std::tuple<float,int[2]> x; With clang++ 3.2, however, the following error is produced: error: array initializer must be an initializer list. If I remove the float type from the tuple declaration, the error disappears. Is the above tuple declaration valid? ( $CXX -std=c++11 -c file.cpp ) 回答1: I don't think there is anything in the Standard that forbids your declaration. However, you will run into problems as soon as you try to

问题 This question already has an answer here : Is initializer list like this legal in C++11? (1 answer) Closed 6 years ago . I'm learning c++ with C++ Primer, 5th ed.. I'm trying to compile a simple c++ program with C++11 features with clang++ but I'm getting compile errors for what should be valid code. This is an example: #include <iostream> #include <vector> #include <string> using namespace std; int main(){ int n = 0; auto *p = &n; //<-- this compiles cout << *p << endl; vector<string>

问题 I'm interested in putting an opening brace for functions (but not if statements and other contexts). For example void foo() { ... } Flamewars aside, is there a good rationale for not doing this? Although I use same-line open-brackets for if/else and smaller blocks, I think in this case visual organization of larger units of code (functions/methods/classes/structs) can trump perfect consistency. Moreover, how do I get clang-format to follow this style? 回答1: As the documentation says, invoke

问题 I have had problems (possibly mine) with template template parameters and clang. The following toy example compiles and runs under g++ 4.7.0, not clang++ 3.0 (based on LLVM 3.0), both ubuntu 12.04. Toy example (test_1.cpp): #include <iostream> #include <memory> struct AFn { void operator()() { ; // do something } }; template<typename T> struct impl { T *backpointer_; }; template<typename S, template <typename> class T> struct implT { T<S> *backpointer_; }; template<typename> class AClass;