Add C compiler base options guidelines

source/development/coding_style.rst

@@ -1,4 +1,97 @@
 .. _coding_guidelines:
 
-Coding Guidelines and Style
-===========================
+Coding Guidelines
+=================
+
+This document specifies a set of coding guidelines, including code style,
+formatting, file structuring and organization that shall be applied when
+contributing code to the Bao project. We strive to ensure that most of the
+guidelines can be automatically checked or even enforced by the CI pipeline and
+minimize guidelines that can not be automatically addressed. In cases where it
+is not feasible to automatically enforce certain guidelines, the responsibility
+lies with the code reviewers and maintainers to ensure that these guidelines
+are adhered to as closely as possible.
+
+C Language
+----------
+
+The coding style and guidelines for C development are heavily influenced and
+constrained by the MISRA C:2012 guidelines, which should take precedence above
+all others in this document or elsewhere.
+
+All C projects should support either the GCC compiler, the Clang compiler or
+both. If one compiler is supported for given project, it must be so for all
+supported target architectures.
+
+For reach guideline we try to provide a set of compiler options which enforce
+the rule, a mapping to a MISRA C:2012 and tools available in the :ref:`CI
+infrastructure <ci>` that can check if this guideline is being adhered to.
+
+Compiler Configuration
+**********************
+
+- The C11 version shall be used.
+
+Compiler options: `-std=c11`.
+MISRA C:2012 : R1.1
+
+- No language extensions shall be allowed.
+
+Compiler options: `-pedantic -pedantic-errors`.
+MISRA C:2012 : R1.1
+
+- Treat all warnings as errors so no warnings can be ignored.
+
+Compiler options: `-Werrors`.
+
+- Enable all recommended warnings.
+
+Compiler options: `-Wall -Wextra`.
+
+Directory and file Structure
+****************************
+
+Pre-processor directives and macros
+***********************************
+
+Header Files
+************
+
+Variable Declarations, Qualifiers and Initializations
+*****************************************************
+
+Functions
+*********
+
+Statements
+**********
+
+Expressions
+***********
+
+Literals
+********
+
+Identifiers and Naming
+**********************
+
+Inline Assembly
+***************
+
+Compiler Directives, Intrinsic and Attributes
+**********************************************
+
+Assertion, Error Handling and Sanity checking
+*********************************************
+
+Comments, Documentation and License
+***********************************
+
+Coding Style and Formatting
+***************************
+
+Keyword Usage
+*************
+
+Libraries and Headers
+*********************