In our experience with a medium-sized project, adding -pipe made no discernible difference in build times. We ran into a couple of problems with it (sometimes failing to delete intermediate files if an error was encountered, IIRC), and so since it wasn’t gaining us anything, we quit using it rather than trying to troubleshoot those … Read more
Just saw this thread while searching for solutions to this problem. I post here for completeness the solution I found… The GCC compiler flags that control unused warnings include: -Wunused-function -Wunused-label -Wunused-parameter -Wunused-value -Wunused-variable -Wunused (=all of the above) Each of these has a corresponding negative form with “no-” inserted after the W which turns … Read more
It depends a bit on what you want: A) If you want to specify which libraries to link to, you can use find_library to find libs and then use link_directories and target_link_libraries to. Of course, it is often worth the effort to write a good find_package script, which nicely adds “imported” libraries with add_library( YourLib … Read more
A. In an imperative programming language, statements are executed in sequence, and each statement may change the program’s state. So analyzing translation units is inherently sequential. An example: Check out how constant propagation might work – a = 5; b = a + 7; c = a + b + 9; You need to go … Read more
It is used if you want to replace a default header with one of your own making, for example, let’s say you want to replace “stdlib.h”. You would create a file called stdlib.h in your project, and that would be included instead of the default header. #include_next is used if you want to add some … Read more
There are two ways to achieve that: Use -rpath linker option: gcc XXX.c -o xxx.out -L$HOME/.usr/lib -lXX -Wl,-rpath=/home/user/.usr/lib Use LD_LIBRARY_PATH environment variable – put this line in your ~/.bashrc file: export LD_LIBRARY_PATH=/home/user/.usr/lib This will work even for a pre-generated binaries, so you can for example download some packages from the debian.org, unpack the binaries and … Read more
Your target triplet indicates that your compiler is configured for the hard-float ABI. This means that the libgcc library will also be hardfp. The error message indicates that at least part of your system is using soft-float ABI. If the compiler has multilib enabled (you can tell with -print-multi-lib) then you can use -mfloat-abi=softfp, but … Read more
This is the chopped down makefile for one of my projects, which compiles the sources in ‘src’ and places the .o files in the directory “obj”. The key bit is the the use of the patsubst() function – see the GNU make manual (which is actually a pretty good read) for details: OUT = lib/alib.a … Read more
It is normally stored in the comment section strings -a <binary/library> |grep “GCC: (” returns GCC: (GNU) X.X.X strip -R .comment <binary> strings -a <binary/library> |grep “GCC: (” returns no output It is not uncommon to strip the .comment (as well as .note) section out to reduce size via strip –strip-all -R .note -R .comment … Read more
If you need that code to work portable then you should cast the argument to unsigned int, as the int type may have a different size than Int32 on some platforms. To answer your question about disabling specific warnings in GCC, you can enable specific warnings in GCC with -Wxxxx and disable them with -Wno-xxxx. … Read more