1. a.k.a how we test Your code
Debugging
a.k.a how we test Your code

2. Some methods Making the compiler (gcc) “furious” Valgrind gdb
Tools provided by the IDE
2017

3. gcc
-Wall – show ‘most’ of the default compiler warnings -Wextra – show even more of the default compiler warnings -pedantic – strict ISO C -Wunreachable-code – code, that will never be run -Wfloat-equal – floating point comparisons -Wshadow – two variables with the same name in the same scope -Wconversion – possible errors due to different types -Wmissing-declaration – no previous declaration of function prototype -g – debugging symbols e.t.c.
2017

4. gdb It can run code line by line
You can observe the values of your variables
See the last lines executed before program crash
Manually assigning values to variables
e.t.c.
More on the subject:
man gdb
internet
2017

5. Valgrind – identifying memory issues
For now:
Using uninitialized variables
Reading from memory locations not belonging to you
Writing to memory locations not belonging to you
Using NULL pointers
Using invalid pointers
In the future:
Memory leaks (lost pointers)
Unreleased resources
Recurring frees to resources
e.t.c
2017

6. How to use it?
Additional flag to compilation -g (same for gdb) gcc -g -o myprogram codefile.c -Wall
-g adds debugging symbols to the compiled binary so that you can for example find the line number that causes the error
To run it valgrind --tool=memcheck --leak-check=full ./myprogram
2017