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From: "isanbard at gmail dot com" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug c/113514] New: Wrong __builtin_dynamic_object_size when using a set local variable Date: Fri, 19 Jan 2024 23:59:50 +0000 [thread overview] Message-ID: <bug-113514-4@http.gcc.gnu.org/bugzilla/> (raw) https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113514 Bug ID: 113514 Summary: Wrong __builtin_dynamic_object_size when using a set local variable Product: gcc Version: 14.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c Assignee: unassigned at gcc dot gnu.org Reporter: isanbard at gmail dot com Target Milestone: --- There appears to be an issue with __builtin_dynamic_object_size() when using a local variable. The following code should output 40 for each __bdos call: $ cat test.c #include <stdio.h> struct s { int a, b, c, d; int foo; #define IDX 2 int blue; char bar[IDX][40]; int baz; int qux; }; int main(int argc, char **argv) { struct s f; #define report(x) fprintf(stderr, #x ": %zu\n", x) report(__builtin_dynamic_object_size(f.bar[1], 1)); report(__builtin_dynamic_object_size(f.bar[1], 3)); report(__builtin_dynamic_object_size(f.bar[argc], 1)); report(__builtin_dynamic_object_size(f.bar[argc], 3)); argc = 1; report(__builtin_dynamic_object_size(f.bar[argc], 1)); report(__builtin_dynamic_object_size(f.bar[argc], 3)); return 0; } However, the last two print 48: $ gcc -O2 test.c && a.out __builtin_dynamic_object_size(f.bar[1], 1): 40 __builtin_dynamic_object_size(f.bar[1], 3): 40 __builtin_dynamic_object_size(f.bar[argc], 1): 40 __builtin_dynamic_object_size(f.bar[argc], 3): 40 __builtin_dynamic_object_size(f.bar[argc], 1): 48 __builtin_dynamic_object_size(f.bar[argc], 3): 48
next reply other threads:[~2024-01-19 23:59 UTC|newest] Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top 2024-01-19 23:59 isanbard at gmail dot com [this message] 2024-01-20 0:12 ` [Bug middle-end/113514] " pinskia at gcc dot gnu.org 2024-01-20 0:18 ` pinskia at gcc dot gnu.org 2024-01-20 0:47 ` isanbard at gmail dot com 2024-01-20 1:15 ` sjames at gcc dot gnu.org 2024-01-22 13:58 ` siddhesh at gcc dot gnu.org 2024-01-22 13:59 ` [Bug middle-end/113514] Imprecise " siddhesh at gcc dot gnu.org
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