With CMake, it’s generally recommended to do an “out of source” build. Create your CMakeLists.txt in the root of your project. Then from the root of your project: mkdir Release cd Release cmake -DCMAKE_BUILD_TYPE=Release .. make And for Debug (again from the root of your project): mkdir Debug cd Debug cmake -DCMAKE_BUILD_TYPE=Debug .. make Release … Read more
(See the history on this answer to get the more elaborate text, but I now think it’s easier for the reader to see real command lines). Common files shared by all below commands $ cat a.cpp extern int a; int main() { return a; } $ cat b.cpp extern int b; int a = b; … Read more
Depends on what you want to do: to read the value as an ascii code, you can write char a=”a”; int ia = (int)a; /* note that the int cast is not necessary — int ia = a would suffice */ to convert the character ‘0’ -> 0, ‘1’ -> 1, etc, you can write … Read more
The standard tool for listing symbols is nm, you can use it simply like this: nm -gD yourLib.so If you want to see symbols of a C++ library, add the “-C” option which demangle the symbols (it’s far more readable demangled). nm -gDC yourLib.so If your .so file is in elf format, you have two … Read more
For Linux and I believe Mac OS X, if you’re using gcc, or any compiler that uses glibc, you can use the backtrace() functions in execinfo.h to print a stacktrace and exit gracefully when you get a segmentation fault. Documentation can be found in the libc manual. Here’s an example program that installs a SIGSEGV … Read more
The difference is caused by the same super-alignment issue from the following related questions: Why is transposing a matrix of 512×512 much slower than transposing a matrix of 513×513? Matrix multiplication: Small difference in matrix size, large difference in timings But that’s only because there’s one other problem with the code. Starting from the original … Read more
gcc and g++ are compiler-drivers of the GNU Compiler Collection (which was once upon a time just the GNU C Compiler). Even though they automatically determine which backends (cc1 cc1plus …) to call depending on the file-type, unless overridden with -x language, they have some differences. The probably most important difference in their defaults is … Read more
In the Old Days (pre-ANSI), predefining symbols such as unix and vax was a way to allow code to detect at compile time what system it was being compiled for. There was no official language standard back then (beyond the reference material at the back of the first edition of K&R), and C code of … Read more
Working for about 4-5 years with software/firmware development and environment testing of miniaturized satellites*, I would like to share my experience here. *(miniaturized satellites are a lot more prone to single event upsets than bigger satellites due to its relatively small, limited sizes for its electronic components) To be very concise and direct: there is … Read more
Looks like you haven’t properly installed the header files and static libraries for python dev. Use your package manager to install them system-wide. For apt (Ubuntu, Debian…): sudo apt-get install python-dev # for python2.x installs sudo apt-get install python3-dev # for python3.x installs For yum (CentOS, RHEL…): sudo yum install python-devel # for python2.x installs … Read more