g++

问题 -Wconversion is producing warnings when I assign a value to a bit field with g++. Source file: struct Foo { public: unsigned int x : 4; unsigned int y : 9; unsigned int z : 17; }; int main(int, char**) { int a = 12; Foo f; f.x = a; f.x = (unsigned int)a; f.x = (unsigned char)a; f.x = (unsigned short)a; f.x = (unsigned)a; f.y = a; f.y = (unsigned int)a; f.y = (unsigned char)a; // no warning, sizeof(char) < 9 f.y = (unsigned short)a; f.y = (unsigned)a; f.z = a; f.z = (unsigned int)a; f.z =

问题 I have such code which works well: #include <algorithm> #include <iostream> char x[11]= "ABCDEFGHIJ"; char y[11]; struct F { char operator () (char c) const { return c+1; } }; int main() { std::transform(x, x+10, y, F()); y[10] = 0; std::cout <<y <<std::endl; } But if I change it to this style: #include <algorithm> #include <iostream> char x[11]= "ABCDEFGHIJ"; char y[11]; int main() { struct F { char operator () (char c) const { return c+1; } }; std::transform(x, x+10, y, F()); y[10] = 0; std

问题 I have such code which works well: #include <algorithm> #include <iostream> char x[11]= "ABCDEFGHIJ"; char y[11]; struct F { char operator () (char c) const { return c+1; } }; int main() { std::transform(x, x+10, y, F()); y[10] = 0; std::cout <<y <<std::endl; } But if I change it to this style: #include <algorithm> #include <iostream> char x[11]= "ABCDEFGHIJ"; char y[11]; int main() { struct F { char operator () (char c) const { return c+1; } }; std::transform(x, x+10, y, F()); y[10] = 0; std

问题 $ file app app: Mach-O universal binary with 2 architectures app (for architecture i386): Mach-O executable i386 app (for architecture x86_64): Mach-O 64-bit executable x86_64 $ gdb app GNU gdb (GDB) 7.6 Copyright (C) 2013 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html> This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. Type "show copying" and "show warranty" for

问题 $ file app app: Mach-O universal binary with 2 architectures app (for architecture i386): Mach-O executable i386 app (for architecture x86_64): Mach-O 64-bit executable x86_64 $ gdb app GNU gdb (GDB) 7.6 Copyright (C) 2013 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html> This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. Type "show copying" and "show warranty" for

问题 I have a problem using Apache Portable Runtime on Ubuntu with GCC 4.8.1 The problem is that the off64_t from <sys/types.h> is not available when compiling with gcc . (When compiling with g++ everything work fine) Does anybody know which compiler switch to use to enable off64_t ? (I know that defining _LARGEFILE_SOURCE _LARGEFILE64_SOURCE avoids the problem, but wondering if this is the right way) To reproduce the error one can simply try to compile the following code: #include <sys/types.h>

问题 I have a DD class template<typename T> class DD : public IEnumerable<T> { typedef IEnumerable<T> Super; typedef std::set<T*> Container; And a method template<typename T> bool DD<T>::Enumerator::Move() { if(!mIt.get()) mIt.reset( new Container::iterator( <----- mContainer.GetContainer().begin() ) ); ... } When I compile the class, I got error: expected type-specifier . What's wrong with the Container::iterator() ? 回答1: Try: new typename Container::iterator When you are in a C++ template, the

问题 How do I set my Visual studio 2008 compiler to GNU GCC. Can I also make it specific to projects? I didn't find any conclusive answer. Thank you. 回答1: You can't use the compiler directly. You can, however, invoke a makefile instead of using the built-in build system. Example of configuration: Install MinGW (I guess this step is already done), including mingw32-make Create a makefile for mingw32-make called MinGWMakefile , with 3 targets: clean , build , and rebuild . This can be very tedious

问题 How do I set my Visual studio 2008 compiler to GNU GCC. Can I also make it specific to projects? I didn't find any conclusive answer. Thank you. 回答1: You can't use the compiler directly. You can, however, invoke a makefile instead of using the built-in build system. Example of configuration: Install MinGW (I guess this step is already done), including mingw32-make Create a makefile for mingw32-make called MinGWMakefile , with 3 targets: clean , build , and rebuild . This can be very tedious

问题 This question already has an answer here : “undefined reference to” errors when linking static C library with C++ code (1 answer) Closed 3 years ago . I realize this question has been asked in a number of ways including this very comprehensive answer but I have looked at many and tried fixing my error to no avail. I am using .cpp and .c files to create a program. I compiled all files with g++, it seemed to have no more linking errors, though it gave me a bunch of C++ errors related to the C