Module Name: src
Committed By: rillig
Date: Wed Apr 13 22:58:19 UTC 2022
Modified Files:
src/usr.bin/xlint/lint1: README.md
Log Message:
lint: remove trailing whitespace from README, add useful breakpoints
To generate a diff of this commit:
cvs rdiff -u -r1.1 -r1.2 src/usr.bin/xlint/lint1/README.md
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/usr.bin/xlint/lint1/README.md
diff -u src/usr.bin/xlint/lint1/README.md:1.1 src/usr.bin/xlint/lint1/README.md:1.2
--- src/usr.bin/xlint/lint1/README.md:1.1 Sun Apr 10 00:42:29 2022
+++ src/usr.bin/xlint/lint1/README.md Wed Apr 13 22:58:18 2022
@@ -1,8 +1,8 @@
-[//]: # ($NetBSD: README.md,v 1.1 2022/04/10 00:42:29 rillig Exp $)
+[//]: # ($NetBSD: README.md,v 1.2 2022/04/13 22:58:18 rillig Exp $)
# Introduction
-To learn how a specific message is triggered, read the corresponding unit
+To learn how a specific message is triggered, read the corresponding unit
test in `tests/usr.bin/xlint/lint1/msg_???.c`.
# Features
@@ -36,7 +36,7 @@ Each node has a type (`type_t`) and a fe
The basic types are `int`, `_Bool`, `unsigned long`, and so on.
A basic type is created by `gettyp(INT)`.
Derived types are created by `block_derive_pointer`,
-`block_derive_array` and `block_derive_function`.
+`block_derive_array` and `block_derive_function`.
(See [below](#memory-management) for the meaning of the prefix `block_`.)
After a type has been created, it should not be modified anymore.
@@ -46,7 +46,7 @@ it needs to be copied using `block_dup_t
## tnode_t
-When lint parses an expressions,
+When lint parses an expressions,
it builds a tree of nodes representing the AST.
Each node has an operator, which defines which other members may be accessed.
The operators and their properties are defined in `ops.def`.
@@ -86,7 +86,7 @@ See `expr_free_all`.
# Null pointers
* Expressions can be null.
- * This typically happens in case of syntax errors or other errors.
+ * This typically happens in case of syntax errors or other errors.
* The subtype of a pointer, array or function is never null.
# Common variable names
@@ -111,13 +111,28 @@ See `expr_free_all`.
| st | subtype |
| op | operator |
+# Debugging
+
+Useful breakpoints are:
+
+| Location | Remarks |
+|-------------------------------|------------------------------------------------------|
+| build_binary in tree.c | Creates an expression for a unary or binary operator |
+| initialization_expr in init.c | Checks a single initializer |
+| expr in tree.c | Checks a full expression |
+| typeok in tree.c | Checks two types for compatibility |
+| vwarning_at in err.c | Prints a warning |
+| verror_at in err.c | Prints an error |
+| assert_failed in err.c | Prints the location of a failed assertion |
+
# Tests
The tests are in `tests/usr.bin/xlint`.
-By default, each test is run with the lint flags `-g` for GNU mode,
+By default, each test is run with the lint flags `-g` for GNU mode,
`-S` for C99 mode and `-w` to report warnings as errors.
Each test can override the lint flags using comments of the following forms:
+
* `/* lint1-flags: -tw */` replaces the default flags.
* `/* lint1-extra-flags: -p */` adds to the default flags.
