| Message ID | 20201116211719.GT3788@tucnak |
|---|---|
| State | New |
| Headers | show |
| Series | c: Reject _Atomic type * as last argument to __builtin_*_overflow [PR90628] | expand |
On Mon, Nov 16, 2020 at 10:17:19PM +0100, Jakub Jelinek via Gcc-patches wrote: > Hi! > > During the __builtin_clear_padding implementation, I've noticed we don't > diagnose _ATomic whatever * as last argument to __builtin_*_overflow. > As the storing by that builtin isn't atomic in any way, I think we should > reject it. > > Bootstrapped/regtested on x86_64-linux, ok for trunk? OK, this makes sense to me. Clang rejects this also. > 2020-11-16 Jakub Jelinek <jakub@redhat.com> > > PR c/90628 > * c-common.c (check_builtin_function_arguments) > <case BUILT_IN_ADD_OVERFLOW>: Diagnose when last argument is pointer > to _Atomic. For the TYPE_READONLY case, adjust message to be usable > for more builtins and argument positions. > > * gcc.dg/builtin-arith-overflow-4.c: New test. > > --- gcc/c-family/c-common.c.jj 2020-11-16 19:33:56.458507220 +0100 > +++ gcc/c-family/c-common.c 2020-11-16 20:23:15.400194347 +0100 > @@ -6133,11 +6133,18 @@ check_builtin_function_arguments (locati > } > else if (TYPE_READONLY (TREE_TYPE (TREE_TYPE (args[2])))) > { > - error_at (ARG_LOCATION (2), "argument 3 in call to function %qE " > - "has pointer to %<const%> type (%qT)", fndecl, > + error_at (ARG_LOCATION (2), "argument %u in call to function %qE " > + "has pointer to %qs type (%qT)", 3, fndecl, "const", > TREE_TYPE (args[2])); > return false; > } > + else if (TYPE_ATOMIC (TREE_TYPE (TREE_TYPE (args[2])))) > + { > + error_at (ARG_LOCATION (2), "argument %u in call to function %qE " > + "has pointer to %qs type (%qT)", 3, fndecl, > + "_Atomic", TREE_TYPE (args[2])); > + return false; > + } > return true; > } > return false; > --- gcc/testsuite/gcc.dg/builtin-arith-overflow-4.c.jj 2020-11-16 20:21:29.859381954 +0100 > +++ gcc/testsuite/gcc.dg/builtin-arith-overflow-4.c 2020-11-16 20:27:13.127519307 +0100 > @@ -0,0 +1,43 @@ > +/* PR c/90628 */ > +/* { dg-do compile } */ > +/* { dg-options "" } */ > + > +_Atomic int a = 1, b = 2, c = 3; > +_Atomic long d = 4, e = 5, f = 6; > +_Atomic long long g = 7, h = 8, i = 9; > + > +void > +f1 () > +{ > + __builtin_add_overflow (a, b, &c); /* { dg-error "argument 3 in call to function '__builtin_add_overflow' has pointer to '_Atomic' type" } */ > +} > + > +void > +f2 () > +{ > + __builtin_sub_overflow (d, e, &f); /* { dg-error "argument 3 in call to function '__builtin_sub_overflow' has pointer to '_Atomic' type" } */ > +} > + > +void > +f3 () > +{ > + __builtin_mul_overflow (g, h, &i); /* { dg-error "argument 3 in call to function '__builtin_mul_overflow' has pointer to '_Atomic' type" } */ > +} > + > +void > +f4 () > +{ > + __builtin_sadd_overflow (a, b, &c); /* { dg-warning "passing argument 3 of '__builtin_sadd_overflow' from incompatible pointer type" } */ > +} > + > +void > +f5 () > +{ > + __builtin_ssubl_overflow (d, e, &f); /* { dg-warning "passing argument 3 of '__builtin_ssubl_overflow' from incompatible pointer type" } */ > +} > + > +void > +f6 () > +{ > + __builtin_smulll_overflow (g, h, &i); /* { dg-warning "passing argument 3 of '__builtin_smulll_overflow' from incompatible pointer type" } */ > +} > > Jakub > Marek
--- gcc/c-family/c-common.c.jj 2020-11-16 19:33:56.458507220 +0100 +++ gcc/c-family/c-common.c 2020-11-16 20:23:15.400194347 +0100 @@ -6133,11 +6133,18 @@ check_builtin_function_arguments (locati } else if (TYPE_READONLY (TREE_TYPE (TREE_TYPE (args[2])))) { - error_at (ARG_LOCATION (2), "argument 3 in call to function %qE " - "has pointer to %<const%> type (%qT)", fndecl, + error_at (ARG_LOCATION (2), "argument %u in call to function %qE " + "has pointer to %qs type (%qT)", 3, fndecl, "const", TREE_TYPE (args[2])); return false; } + else if (TYPE_ATOMIC (TREE_TYPE (TREE_TYPE (args[2])))) + { + error_at (ARG_LOCATION (2), "argument %u in call to function %qE " + "has pointer to %qs type (%qT)", 3, fndecl, + "_Atomic", TREE_TYPE (args[2])); + return false; + } return true; } return false; --- gcc/testsuite/gcc.dg/builtin-arith-overflow-4.c.jj 2020-11-16 20:21:29.859381954 +0100 +++ gcc/testsuite/gcc.dg/builtin-arith-overflow-4.c 2020-11-16 20:27:13.127519307 +0100 @@ -0,0 +1,43 @@ +/* PR c/90628 */ +/* { dg-do compile } */ +/* { dg-options "" } */ + +_Atomic int a = 1, b = 2, c = 3; +_Atomic long d = 4, e = 5, f = 6; +_Atomic long long g = 7, h = 8, i = 9; + +void +f1 () +{ + __builtin_add_overflow (a, b, &c); /* { dg-error "argument 3 in call to function '__builtin_add_overflow' has pointer to '_Atomic' type" } */ +} + +void +f2 () +{ + __builtin_sub_overflow (d, e, &f); /* { dg-error "argument 3 in call to function '__builtin_sub_overflow' has pointer to '_Atomic' type" } */ +} + +void +f3 () +{ + __builtin_mul_overflow (g, h, &i); /* { dg-error "argument 3 in call to function '__builtin_mul_overflow' has pointer to '_Atomic' type" } */ +} + +void +f4 () +{ + __builtin_sadd_overflow (a, b, &c); /* { dg-warning "passing argument 3 of '__builtin_sadd_overflow' from incompatible pointer type" } */ +} + +void +f5 () +{ + __builtin_ssubl_overflow (d, e, &f); /* { dg-warning "passing argument 3 of '__builtin_ssubl_overflow' from incompatible pointer type" } */ +} + +void +f6 () +{ + __builtin_smulll_overflow (g, h, &i); /* { dg-warning "passing argument 3 of '__builtin_smulll_overflow' from incompatible pointer type" } */ +}