Common pitfalls
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This section discusses some of the common mistakes that a C programmer should be aware of and should avoid making. For more on some unexpected problems and their causes, please see Undefined behavior
Related Examples
- Adding a semicolon to a #define
- Checking logical expression against 'true'
- Comparing floating point numbers
- Copying too much
- Doing extra scaling in pointer arithmetic
- Floating point literals are of type double by default
- Forgetting to allocate one extra byte for \0
- Forgetting to copy the return value of realloc into a temporary
- Forgetting to free memory (memory leaks)
- Ignoring return values of library functions
- Incautious use of semicolons
- Macros are simple string replacements
- Mistakenly writing = instead of == when comparing
- Misunderstanding array decay
- Mixing signed and unsigned integers in arithmetic operations
- Multi-line comments cannot be nested
- Newline character is not consumed in typical scanf() call
- Overstepping array boundaries
- Passing unadjacent arrays to functions expecting "real" multidimensional arrays
- Recursive function — missing out the base condition
- Undefined reference errors when linking
- Using character constants instead of string literals, and vice versa