GCC accepts this: void foo() { goto *1; } The "Labels as Values" section of the doc states that indirect gotos take "Any expression of type void *". 1 is not of type void*. it looks like gcc accepts anything convertible to a pointer type. Trying to jump to a structure yields: t.c:15: error: cannot convert to a pointer type -Chris
Confirmed, not a regression as far as the eyes can see.
I've always used `goto *123;' on embedded targets as a feature to be able to jump to a constant address. This particularly useful feature should not be removed. Is a simple change of syntax being suggested, such as `goto *(void *)123;'? Dereferencing a void pointer looks strange to me, but I guess no stranger than dereferencing an integer.
*** Bug 69704 has been marked as a duplicate of this bug. ***
Mine, I have a patch.
Created attachment 51472 [details] Patch which I am testing It passes all of gcc.dg/dg.exp I am doing a full bootstrap/test right now.
Patch finally submitted: https://gcc.gnu.org/pipermail/gcc-patches/2021-September/579792.html
The trunk branch has been updated by Andrew Pinski <pinskia@gcc.gnu.org>: https://gcc.gnu.org/g:e12f66d96fe41c8ef8a0d01b6a8394cd6bce3978 commit r12-3947-ge12f66d96fe41c8ef8a0d01b6a8394cd6bce3978 Author: Andrew Pinski <apinski@marvell.com> Date: Fri Sep 17 04:59:03 2021 +0000 c: [PR32122] Require pointer types for computed gotos So GCC has always accepted non-pointer types in computed gotos but that was wrong based on the documentation: Any expression of type void * is allowed. So this fixes the problem by requiring the type to be a pointer type. OK? Bootstrapped and tested on x86_64-linux-gnu with no regressions. PR c/32122 gcc/c/ChangeLog: * c-parser.c (c_parser_statement_after_labels): Pass the c_expr instead of the tree to c_finish_goto_ptr. * c-typeck.c (c_finish_goto_ptr): Change the second argument type to c_expr. * c-tree.h (c_finish_goto_ptr): Likewise. Error out if the expression was not of a pointer type. gcc/testsuite/ChangeLog: * gcc.dg/comp-goto-5.c: New test. * gcc.dg/comp-goto-6.c: New test.
Fixed.