From: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
To: linux-sparse@vger.kernel.org
Cc: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Subject: [PATCH] warn when taking the address of a built-in function
Date: Sat, 17 Oct 2020 01:11:26 +0200 [thread overview]
Message-ID: <20201016231126.23899-1-luc.vanoostenryck@gmail.com> (raw)
Built-in functions are meant to be expanded by the compiler. As such,
they don't have an address.
So, issue an error when trying take the address of a built-in function.
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
---
evaluate.c | 4 ++++
validation/builtin-arith.c | 25 +++++++++++++++----------
2 files changed, 19 insertions(+), 10 deletions(-)
diff --git a/evaluate.c b/evaluate.c
index 3ff76fa85e14..d742025287cd 100644
--- a/evaluate.c
+++ b/evaluate.c
@@ -1787,6 +1787,8 @@ static struct symbol *degenerate(struct expression *expr)
expression_error(expr, "strange non-value function or array");
return &bad_ctype;
}
+ if (ctype->builtin)
+ sparse_error(expr->pos, "taking the address of built-in function '%s'", show_ident(ctype->ident));
*expr = *expr->unop;
ctype = create_pointer(expr, ctype, 1);
expr->ctype = ctype;
@@ -1807,6 +1809,8 @@ static struct symbol *evaluate_addressof(struct expression *expr)
return NULL;
}
ctype = op->ctype;
+ if (ctype->builtin)
+ sparse_error(expr->pos, "taking the address of built-in function '%s'", show_ident(ctype->ident));
*expr = *op->unop;
mark_addressable(expr);
diff --git a/validation/builtin-arith.c b/validation/builtin-arith.c
index 7aabbcb1bd58..3ce593045b37 100644
--- a/validation/builtin-arith.c
+++ b/validation/builtin-arith.c
@@ -31,22 +31,27 @@ void test(void (*fun)(void))
/*
* check-name: builtin arithmetic
* check-command: sparse -Wno-decl $file
- * check-known-to-fail
*
* check-error-start
-builtin-arith.c:10:xx: error: ...
-builtin-arith.c:11:xx: error: ...
+builtin-arith.c:10:14: error: taking the address of built-in function '__builtin_trap'
+builtin-arith.c:11:13: error: taking the address of built-in function '__builtin_trap'
+builtin-arith.c:12:14: error: taking the address of built-in function '__builtin_trap'
+builtin-arith.c:13:14: error: taking the address of built-in function '__builtin_trap'
builtin-arith.c:13:29: error: arithmetics on pointers to functions
+builtin-arith.c:14:14: error: taking the address of built-in function '__builtin_trap'
builtin-arith.c:14:29: error: arithmetics on pointers to functions
+builtin-arith.c:15:14: error: taking the address of built-in function '__builtin_trap'
builtin-arith.c:15:29: error: arithmetics on pointers to functions
-builtin-arith.c:18:xx: error: ...
-builtin-arith.c:19:xx: error: ...
-builtin-arith.c:21:xx: error: ...
-builtin-arith.c:22:xx: error: ...
-builtin-arith.c:23:xx: error: ...
-builtin-arith.c:24:xx: error: ...
-builtin-arith.c:25:xx: error: ...
+builtin-arith.c:18:21: error: taking the address of built-in function '__builtin_trap'
+builtin-arith.c:19:29: error: taking the address of built-in function '__builtin_trap'
+builtin-arith.c:21:14: error: taking the address of built-in function '__builtin_trap'
+builtin-arith.c:22:14: error: taking the address of built-in function '__builtin_trap'
+builtin-arith.c:23:14: error: taking the address of built-in function '__builtin_trap'
+builtin-arith.c:24:21: error: taking the address of built-in function '__builtin_trap'
+builtin-arith.c:25:21: error: taking the address of built-in function '__builtin_trap'
+builtin-arith.c:27:9: error: taking the address of built-in function '__builtin_trap'
builtin-arith.c:27:24: error: subtraction of functions? Share your drugs
+builtin-arith.c:28:15: error: taking the address of built-in function '__builtin_trap'
builtin-arith.c:28:13: error: subtraction of functions? Share your drugs
* check-error-end
*/
--
2.28.0
reply other threads:[~2020-10-16 23:11 UTC|newest]
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