I am learning C from Head First C. One short exercise is connected with Makefile. The source code is:
oggswing: oggswing.c oggswing.h
gcc oggswing.c -o oggswing
swing.ogg: whitennerdy.ogg oggswing
oggswing whitennerdy.ogg swing.ogg
(Please assume that the indented lines start with the required tab.)
I do not understand oggswing whitennerdy.ogg swing.ogg. There isn’t any command like gcc or the other. I can't find any solutions why is that correct? Could you help me?
oggswing is the result of building oggswing.c.
It can then be executed to process the two .ogg files (in whatever way it implements).
And oggswing will be built because it is a dependency for the target swing.ogg.
Related
I'm having issues with a c program that I want to debug.
I would like to know how to get a file that contains every lines of my executable, so I can later set breakpoints with gdb in it.
Thanks :)
For GCC specify -g when compiling.
More here: https://gcc.gnu.org/onlinedocs/gcc/Debugging-Options.html
I once tried to compile a C program I made that was for a chess game (thanks to YouTube's Bluefever Software for the tutorial), but when I went to compile the program, I executed this line of code:
C:\TDM-GCC-64\>gcc Chess/chess.c Chess/init.c -o chess
The compiling worked (there were no syntax errors or anything), but when I got to my file directory, I saw this (circled in blue):
An unexpected application (but there were no viruses!):
How did this happen? It may had something to do with the line I was compiling, but what is the "intel" behind this?
It is normal for the compiler to generate an application!
What is surprising is the location for the executable, it should have been generated in the parent directory:
C:\TDM-GCC-64\> gcc Chess/chess.c Chess/init.c -o chess
The explanation is interesting:
You are using the Windows operating system, where the filenames are case insensitive.
You instructed gcc to generate the executable into chess, but this is the name of the Chess directory. In this case, gcc generates the executable in the named directory and gives it a name that is the basename of the first source file chess.c -> chess.
Furthermore, the application name really is chess.exe in Windows, but the default setting for the file manager is to not display file extensions. This is a very unfortunate choice. I suggest you change this setting in the Windows/File Explorer Options window to always show file extensions. This will allow you to distinguish chess.c, chess.exe and chess.h more easily.
You have a Makefile in the Chess directory, you should use the make command to build the executable:
C:\TDM-GCC-64\> make -C Chess
Or simply cd to the Chess subdirectory and type:
C:\TDM-GCC-64\Chess> make
That's the file you told the compiler to make.
The -o option to gcc is the output file. In this case, you told it to create an executable file named chess. And that's exactly what was created.
The compiler is automatically creating an executable file while compiling.
Could Someone kindly tell me how can I profile single lines or blocks of code of a program in C with GNU profiler?
I used gprof ./a.out gmon.out which gives me flat profile and Call graph. However, I would like to see lines that are more frequently accessed.
Thanks,
This is probably one of those things that you just don't know the term you should've googled, so I'll answer it:
The term you are looking for is "annotation"-you want to annotate the source and see the line by line hits in the code.
Calling gprof with the -A flag will dump out the samples on each line that were caught.
See Also:
https://sourceware.org/binutils/docs/gprof/Annotated-Source.html
Ok, I'll post this answer so if some newbie like me searched for it can find it faster :)
here are the steps: source
gcc -fprofile-arcs -ftest-coverage fourcefile.c
(At the end of compilation files *.gcno will be produced)
Run the executable.
Run gcov: gcov sourcefile.c
(At the end of running, a file (*.gcov) will be produced which contains which contains all the required info)
As a part of my college project, we're supposed to develop a C compiler. The lexer and parser part is over - the tools Flex & Bison made our uphill task much simpler. Now where we're stuck is that we are unable to move on with the project. How exactly does one proceed once we have these three files in hand:
y.tab.h
y.tab.c
lex.yy.c
We also managed to produce an executable by using the following command on the DOS prompt
gcc lex.yy.c y.tab.c -o example1
and i got the executable example.exe...
Now how to proceed to get the compiler running? How to get it to build user C code?
You should check whether your example.exe can read a C program and report any syntax errors.
If it cannot, fix your .y and/or .l files and try again.
If it can, great, you have a working parser. Now turn it into a working compiler. Keep adding code, known as semantic actions, to the .y file, implementing more and more of the compiler's functionality. First, make sure you can report semantic errors, such as invalid types or missing declarations. Then implement assembly code generation.
When the .y file becomes too big, turn some code into functions and move them to separate .c files.
This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
Is there an interpreter for C?
I want to practice C a bit and I would like to have something that allows to write and test C code quickly. I want to have an interpreter with UI where I can write my code and execute it.
Are there any good solutions for that?
The closest solution to what you are looking for seems to be the C shell (CSH) or C Scripting Language (CSL).
Alternatively, have an editor open where you will write your C sample, then have console window where you will execute your favourite C compiler. The idea is to have simple workflow like this:
$ gvim test.c
$ gcc test.c
$ ./a.out
Don't forget, C is not a scripting language.
However, you may find JIT compiler for C, C++, and the likes discussion helpful.
Though "interpreters" per se don't exist (or not practically), I'd advise on using a modern IDE. Eclipse + CDT allows you to have "on the fly compilation", just like in java. Your project is ready to run whenever you are, with reduced latency due to compilation (if you have a decent computer).
For other answers, I advise on NOT using directly gcc test.c. Use a makefile or use at least gcc -Wall -g -o myapp test.c top have additional information during compilation (useful as C has many more pitfalls than python). Please note as well that testis astandard program and that . might not be in your PATH : myapp is a better name than test ;-)
There is Cling. Never used it, so I can't really tell you more, but it looks like what you are looking for.
You might also find other lead in this question: Is there an interpreter for C?
you can take a look at : http://codepad.org/
or the easy way is to create a sh script like :
vim $1 ; gcc $1 ; ./a.out
You can't interpret C++ code as far as I know...
What you could do (and what I do when I quickly need to write some simple things ) is set up a simple make file and open a new file with some simple text editor like Kate that has a console plugin. Then you can write some code and type "make" to see the result of your code in the konsole / whichever shell you are using