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The scanner currently (f89a9e2) assumes the source code is ASCII only. Supporting UTF-8 should increase the scanner's complexity, and so it should be done later rather than now, when more important features will already be implemented by then.

This issue is used to keep track of the parser development.

Scope functionality

• Be able to lookup declarations

Expressions

• Primary expressions
• Postfix expressions
• Unary expressions
• Cast expressions
• Multiplicative expressions
• Additive expressions
• Shift expressions
• Relational expressions
• Equality expressions
• AND expressions
• XOR expressions
• OR expressions
• Logical AND expressions
• Logical OR expressions
• Conditional expressions
• Assignment expressions
• Expressions
• Constant expressions

Declarations

• Basic declarations
• Declaration specifiers
• Init declarator
• Struct or union declarations
• Enum declarations
• Declarators
• Abstract declarators
• Typedef
• Initializers
• Static assert

Statements

• Labeled statements
• Compound statements
• Expression statements
• Selection statements
• Iteration statements
• Jump statements

External definitions

• Function definitions
• Translation units

There are two approaches to end-to-end validations that we wish to have: execution behavior, and assembly output. The first one compiles a set of C source codes, and runs the executable to check against an expected output (i.e., stdout, and stderr). The second one also compiles a set of C source codes, but instead of executing the program, it compares the assembly output against an expected one.

We could work on a validation suite ourselves for the first approach, but that sounds like a lot of work, and I'm no standard specialist either. We are inevitably going to work on the second approach ourselves, as that's a result of test driven development.

There are a few options out there that we could check out:

• Plum Hall: http://www.plumhall.com/stec.html
• c-testsuite: https://github.com/c-testsuite/c-testsuite
• GCC C Tests: https://gcc.gnu.org/onlinedocs/gccint/C-Tests.html#C-Tests

Line comments should be skipped during the scanning.

Trigraphs aren't important right now though, so it should be taken care of in the far future.

1. https://llvm.org/docs/CommandGuide/lit.html
2. https://llvm.org/docs/TestingGuide.html
3. https://llvm.org/docs/CommandGuide/FileCheck.html