Module Name: src
Committed By: rillig
Date: Mon Jul 26 18:06:43 UTC 2021
Modified Files:
src/tests/usr.bin/xlint/lint1: expr_precedence.c expr_precedence.exp
Log Message:
tests/lint: show bug in conditional expression (since 2021-07-15)
Since cgram.y 1.325 from 2021-07-15, conditional expressions did not
accept a comma-expression in the then-branch anymore. In practice, this
is an edge case though since comma expressions are rare.
To generate a diff of this commit:
cvs rdiff -u -r1.5 -r1.6 src/tests/usr.bin/xlint/lint1/expr_precedence.c \
src/tests/usr.bin/xlint/lint1/expr_precedence.exp
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/tests/usr.bin/xlint/lint1/expr_precedence.c
diff -u src/tests/usr.bin/xlint/lint1/expr_precedence.c:1.5 src/tests/usr.bin/xlint/lint1/expr_precedence.c:1.6
--- src/tests/usr.bin/xlint/lint1/expr_precedence.c:1.5 Mon Jul 26 17:27:22 2021
+++ src/tests/usr.bin/xlint/lint1/expr_precedence.c Mon Jul 26 18:06:43 2021
@@ -1,4 +1,4 @@
-/* $NetBSD: expr_precedence.c,v 1.5 2021/07/26 17:27:22 rillig Exp $ */
+/* $NetBSD: expr_precedence.c,v 1.6 2021/07/26 18:06:43 rillig Exp $ */
# 3 "expr_precedence.c"
/*
@@ -51,3 +51,27 @@ assignment_associativity(int arg)
left = arg;
}
+
+void
+conditional_associativity(_Bool cond1, _Bool cond2, int a, int b, int c)
+{
+ /* The then-expression can be an arbitrary expression. */
+ var = cond1 ? cond2 ? a : b : c;
+ var = cond1 ? (cond2 ? a : b) : c;
+
+ /* The then-expression can even be a comma-expression. */
+ /* expect+1: error: syntax error ',' [249] *//* FIXME */
+ var = cond1 ? cond2 ? a, b : (b, a) : c;
+
+ var = cond1 ? a : cond2 ? b : c;
+ /*
+ * In almost all programming languages, '?:' is right-associative,
+ * which allows for easy chaining.
+ */
+ var = cond1 ? a : (cond2 ? b : c);
+ /*
+ * In PHP, '?:' is left-associative, which is rather surprising and
+ * requires more parentheses to get the desired effect.
+ */
+ var = (cond1 ? a : cond2) ? b : c;
+}
Index: src/tests/usr.bin/xlint/lint1/expr_precedence.exp
diff -u src/tests/usr.bin/xlint/lint1/expr_precedence.exp:1.5 src/tests/usr.bin/xlint/lint1/expr_precedence.exp:1.6
--- src/tests/usr.bin/xlint/lint1/expr_precedence.exp:1.5 Mon Jul 26 17:27:22 2021
+++ src/tests/usr.bin/xlint/lint1/expr_precedence.exp Mon Jul 26 18:06:43 2021
@@ -2,3 +2,4 @@ expr_precedence.c(15): error: syntax err
expr_precedence.c(18): error: non-constant initializer [177]
expr_precedence.c(35): error: 'var' undefined [99]
expr_precedence.c(35): error: syntax error '=' [249]
+expr_precedence.c(64): error: syntax error ',' [249]
