eddieantonio / induce-gcc-errors

Induce the top 20 C errors in gcc

C errors

This repository induces the top 20 C error messages from Cormac Murray's 2019 MSc Thesis.

How to use

You will need:

• gcc-12
• aha (to generate coloured HTML)

Then run:

make

Errors

This list of errors comes from §8.1.2 (page 92) from Cormac's thesis. The "e" codes were invented for the purposes of the thesis. The errors are ranked from most frequently occurring to least frequently occurring. These are messages that appear at ANY level in the output (not just the first error message).

I used gcc-12 on macOS, but I believe Cormac's errors come from an Ubuntu machine—thus linker errors might be formatted differently.

Rank	Code	Kind	Error Category
1	e1001	Compiler	<x> undeclared <...>
2	e1002	Compiler	expected <x> before <y>
3	e1007	Compiler	stray <x> in program
4	e1004	Compiler	expected expression before <x>
5	e1010	Compiler	unknown type name <x>
6	e1005	Compiler	expected declaration or statement at end of input
7	e1008	Compiler	expected identifier or ( before <x>
8	e1006	Compiler	expected =, ,, ;, asm, __attribute__ before <x>
9	e1023	Compiler	request for member in something not a structure or union
10	e1044	Compiler	expected declaration specifiers or '...' before <x>
11	e1012	Compiler	<x> has no member named <y>
12	e1003	Linker	undefined reference to <x>
13	e1013	Compiler	invalid type argument of <...>
14	e1030	Compiler	expected <x> before <...> constant
15	e1017	Compiler	too few arguments to function <x>
16	e1011	Compiler	lvalue required as <...>
17	e1022	Compiler	expected declaration specifiers or '...' before <...> constant
18	e1034	Compiler	expected declaration specifiers before <x>
19	e1015	Compiler	missing terminating <x> character
20	e1020	Compiler	redefinition of <x>
21	e1009	Invocation	<x>: No such file or directory
22	e1014	Compiler	conficting types for <x>

Notes

There are 20 compiler errors, but a linker error and an invocation error are within the top 22 messages recorded within Cormac's list. It might be undesirable to mix linker and invocation errors, so I have collected the top 22 messages from the list.

e1034: expected declaration specifiers before 'if'

I have absolutely no idea how to get this without a cascading error. This error message can be induced by writing a statement after the function declaration, but missing the opening curly brace for a function definition.

18-e1034.c: In function 'main':
18-e1034.c:2:5: error: expected declaration specifiers before 'if'
    2 |     if (argc == 1)
      |     ^~
18-e1034.c:4: error: expected '{' at end of input

e1003: undefined reference to <x>

This is a linker error, and as such, is dependent on the platform's linker. I have committed the version from a glibc-style linker.

e1015: missing terminating " character

I cannot seem to get this without:

1. a warning with the same message
2. a cascading error, due to error recovery