I have a big project which after make ends up with 1GB of executables and libs.
I use standard workflow: autogen, configure, make, make install. The problem is after this all the files ends up in default system directories along with other installed software and I can't selectively use strip to reduce the size of the project's executable and libraries. What is a proper workflow to strip symbols after make is done? Are there options for this in configure other then visiting each source directory and do it on my own after make is over?
Related
After an error occurred because of a missing flag or incorrectly set environment variable, is it possible to continue compiling once the mistake has been fixed?
I regularly use CMake and make to compile toolkits that take quite a while to compile and, also regularly, I accidentally set variables incorrectly in the process. Just now for example, I was attempting to include OpenInventor headers which on my machine are located in the directory /Users/user/software/prod/coin/include/Inventor.
I mistakenly passed
-DINVENTOR_INCLUDE_DIR=/Users/user/software/prod/coin/include/Inventor
rather than the correct
-DINVENTOR_INCLUDE_DIR=/Users/user/software/prod/coin/include
This only became an issue after 30 minutes when about 95% of the compilation was completed. Because I knew that reconfiguring using CMake would force a recompilation from scratch, I tried to add -I/Users/user/software/prod/coin/include to CMAKE_CXX_FLAGS in CMakeCache.txt but to no avail–it still recompiled from scratch. Since only a single source file actually includes the headers in question, it would be desirable if I could start compiling from the point where it exited with an error once the relevant path has been corrected. How can I do this and, as an aside, why does it force the compiler to start from scratch?
I'm using CMake version 3.11.1 and clang (Apple LLVM version 9.1.0) on macOS 10.13
CMake does not need to recompile everything just because it regenerates its makefiles. It will still perform normal make avoidance operations. However CMake does track the compiler options used to build each target, so if you make a change in the compiler options for all the targets then they'll all need to be rebuilt.
If this compiler option is only needed for one target, you can add it to just that target an no others, with something like this:
set_property(SOURCE my_source.c APPEND PROPERTY
COMPILE_FLAGS -I/foo/bar)
then it should only rebuild that one source file.
CMake looks for files' "last modified" times to decide which files need recompilation. But if you change the input to CMake itself, then it needs to regenerate the Makefiles and therefore recompile everything. But still, one hack may be possible...
CMake stores information about the include directories and the libraries to be linked in various text files in the build directory. So one hack (not recommended, but works) can be to modify these text files.
In the particular example that you mentioned, the hack would be to search and replace all occurrences of /Users/user/software/prod/coin/include/Inventor with /Users/user/software/prod/coin/include in all the files of the build directory.
(As an aside, if you don't already know, you can use make -j <n> to build using multiple threads which can considerably decrease the build times.)
I'm using Bison and Flex in an Xcode project. I didn't want to put the generated files under source control, so I was happy to find that Xcode natively supports Bison/Flex files, generating the parsers on-the-fly in its derived data folder. So far so good.
However, Xcode uses an embedded old Bison version (2.3):
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/yacc
which doesn't yet support the %define api.pure full directive. Since this bison executable is under the Xcode.app bundle I can't replace it, so I installed the latest version via Brew and added it to my $PATH through ~/.bash_profile (~/.bashrc also sources my bash profile). So in bash I can say:
$ which bison
/usr/local/Cellar/bison/3.0.4/bin//bison
However, Xcode still uses it's own version... I suppose the path to the internal bison is hardcoded.
My second approach was to create a custom build rule for Yacc files, and run the correct version of bison from there. This time the problem was that as Xcode ran my custom build rule, it immediately tried to build the resulting C files. The generated C files would however depend on the header file yet to be generated by Flex, because that's where e.g. yyscan_t is declared (used by Bison in the generated C file). But on the other hand, Flex-generated C files also include the Bison-generated header, so compiling with Flex first doesn't help...
What I need is to first only generate the Flex and Bison headers/sources and then build them along with the rest of the project.
How can I achieve this?
I've managed to solve the issue by putting the *.l and *.y files under a *.parser folder and adding that folder to the project. Then I removed the *.l and *.y files added the folder to the compiled sources:
And then made a Build Rule for *.parser like this:
This enables me to first run yacc and lex and only then will the resulting *.cpp files be passed to the compilation step.
If you go to your build target, Build Phases, and click the + on the bar with the search box on it, you can add a New Run Script Phase. You can then drag that above your current Compile Sources phase. You can do whatever you want in that script phase, and it will run before compilation starts.
This is a bit of a Zombie, but if I ever come back here again, I will want to see the answer.
Certainly from XCode 12 (probably before) the answer is trivially easy.
(1) Go to build settings
(2a) Press the + for a brand new setting variable.
(2b) Change the NAME to YACC, and it's VALUE to /usr/local/bin/bison (or whatever path you need for brew).
(3a) Press the + for a brand new setting variable.
(3b) Change the NAME to LEX, and it's VALUE to /usr/local/bin/flex (or whatever path you need for brew).
(4+) use the YACC/LEX settings for flags that you want to use.
I've managed to do it with custom build rules, using bison installed from brew and flex that comes with macOS, not the one bundled with Xcode. I'm not sure if my problem was the same as yours, but if you want to take a look my project is on GitHub.
I followed this install wget tutorial,
After I ran this
./configure --with-ssl=openssl
It ran so many checks, what exactly it did? Did it change anything in my system?
If it does, then, is it safer or more fault prove to use the package management tool like MacPort or such so that such 'configure' will not be done manually like this or does those tool do the same thing in order to make wget work?
Sorry, I am pretty noob on shell commands.
Thanks
It's part of the build process. The configure script collects information about your system and build options into a local file, nothing more.
Typically, this script is created by autoconf and is used to figure out whether the prerequisites for a build are properly installed, etc. It will collect this into a file config.save and also possibly generate a makefile and/or other build infrastructure in order for make to be able to concentrate on compiling and linking the source files.
Neither configure nor make should be expected to change anything outside of the directory tree where you run them.
Conventionally, make install will copy the final build artefacts into place so that other parts of your system can find them and use them.
See also http://www.edwardrosten.com/code/autoconf/
A prepackaged binary will already have been built on a remote system before it was packaged (though there are package managers which allow or require you to build locally; Gentoo Linux famously uses the latter approach) and is often the simplest way to get a tool if you don't have special requirements, such as building with a specific SSL version, or disabling SSL entirely, or getting a bleeding edge version before anybody has packaged it.
I'm trying to get something of an environment on a usb stick to develop C++ code in. I plan to use other computers, most of the time linux, to work on this from a command line using g++ and make.
The problem is I need to use some libraries, like Lua and OpenGL, which the computers don't have. I cannot add them to the normal directories, I do not have root on these computers. Most of the solutions I've found involve putting things in /usr/lib/ and the like, but I cannot do that. I've also attempted adding options like '-L/media//lib', which is where they are kept, and it didn't work. When compiling, I get the same errors I got when first switching to an OS with the libraries not installed.
Is there somewhere on the computer outside of /usr/ I can put them, or a way to make gcc 'see' them?
You need more than the libraries to be able to compile code utilizing those libraries. (I'm assuming Linux here, things might be slightly different on e.g. OSX,BSDs,Cygwin,Mingw..)
Libraries
For development you need these 3 things when your code uses a library:
The library header files, .h files
The library development files, libXXX.so or libXXX.a typically
The library runtime files , libXXX.so.Y where Y is a version number. These are not needed if you statically link in the library.
You seem to be missing the header files (?) Add them to your usb stick, say under /media/include
Development
Use (e.g.) the compiler flag -I/media/include when compiling source code to refer to a non-standard location of header files.
Use the compiler/linker flag -L/media/lib to refer to non-standard location of libraries.
You might be missing the first step.
Running
For dynamically linked libraries, the system will load those only from default locations, typically /lib/ , /usr/lib/
Learn the ldd tool to help debug this step.
You need to tell the system where to load additional libraries when you're running a program, here's 3 alternatives:
Systemwide: Edit /etc/ld.so.conf and add /media/libs there. Run ldconfig -a afterwards.
Local, to the current shell only. set the LD_LIBRARY_PATH environment variable to refer to /media/lib, run export LD_LIBRARY_PATH=/media/lib
Executable: Hardcode the non-standard library path in the executable. You add this to the linking step when creating your executable: -Wl,-rpath,/media/lib
Etc.
There could be other reasons things are not working out, if so,
show us the output of ls -l /media/libs , and where you put the library header files, the command line you use to compile/link, and the exact errors you get.
Missing the headers and/or development libraries (for dynamic libraries there is usually a symlink from a libXXX.so to a libXXX.so.Y , the linker needs the libXXX.so , it will not look directly at libXXX.so.Y)
using libraries not compatible with your current OS/architecture. (libraries compiled on one linux distro is often not compatible with another distro, or even another minor version of the same distro)
using an usb stick with a FAT32 filesystem, you'll get in trouble with symlinks..
A small change in a 1000's of lines of code leads to running the ./configure again on the entire software.
Is there any alternative, where we can compile only the changed file and the files associated with it?
If you have a sane Makefile.am with proper dependencies, running ./configure and make should only recompile files that depend on the touched file. So make already does what you are asking for.
If your Makefiles are not sane (e.g. they only work if you run make clean) and you are compiling C or C++ sources, using ccache might give you a speed gain. With ccache only the preprocessor part is run and its output compared to a cache of compile outputs. If nothing changed in the file or its includes it won't be recompiled. Properly installed it is run in a transparent way.