[clang] 4a47da2 - [Sema] turns -Wfree-nonheap-object on by default
David Blaikie via cfe-commits
cfe-commits at lists.llvm.org
Sat Apr 3 16:29:34 PDT 2021
Looks like this has a false positive (that's firing on some mlir code,
committed a workaround in 499571ea835daf786626a0db1e12f890b6cd8f8d )
like this:
$ cat test.cpp
#include <stdlib.h>
void f1(int & x) { free(&x); }
int main() { f1(*(int*)malloc(sizeof(int))); }
Could you fix that? (& then revert the workaround)
On Fri, Jan 15, 2021 at 1:44 PM Christopher Di Bella via cfe-commits
<cfe-commits at lists.llvm.org> wrote:
>
>
> Author: Christopher Di Bella
> Date: 2021-01-15T21:38:47Z
> New Revision: 4a47da2cf440c2f2006d9b04acfef4292de1e263
>
> URL: https://github.com/llvm/llvm-project/commit/4a47da2cf440c2f2006d9b04acfef4292de1e263
> DIFF: https://github.com/llvm/llvm-project/commit/4a47da2cf440c2f2006d9b04acfef4292de1e263.diff
>
> LOG: [Sema] turns -Wfree-nonheap-object on by default
>
> We'd discussed adding the warning to -Wall in D89988. This patch honours that.
>
> Added:
>
>
> Modified:
> clang/include/clang/Basic/DiagnosticGroups.td
> clang/include/clang/Basic/DiagnosticSemaKinds.td
> clang/test/Analysis/NewDelete-intersections.mm
> clang/test/Analysis/free.c
>
> Removed:
>
>
>
> ################################################################################
> diff --git a/clang/include/clang/Basic/DiagnosticGroups.td b/clang/include/clang/Basic/DiagnosticGroups.td
> index d500ab321058..04ba89aa457e 100644
> --- a/clang/include/clang/Basic/DiagnosticGroups.td
> +++ b/clang/include/clang/Basic/DiagnosticGroups.td
> @@ -110,6 +110,7 @@ def FloatConversion :
> FloatZeroConversion]>;
>
> def FrameAddress : DiagGroup<"frame-address">;
> +def FreeNonHeapObject : DiagGroup<"free-nonheap-object">;
> def DoublePromotion : DiagGroup<"double-promotion">;
> def EnumTooLarge : DiagGroup<"enum-too-large">;
> def UnsupportedNan : DiagGroup<"unsupported-nan">;
>
> diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td
> index 7d36397a7993..e93657898f58 100644
> --- a/clang/include/clang/Basic/DiagnosticSemaKinds.td
> +++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td
> @@ -7609,7 +7609,7 @@ def err_no_typeid_with_fno_rtti : Error<
> def err_no_dynamic_cast_with_fno_rtti : Error<
> "use of dynamic_cast requires -frtti">;
> def warn_no_dynamic_cast_with_rtti_disabled: Warning<
> - "dynamic_cast will not work since RTTI data is disabled by "
> + "dynamic_cast will not work since RTTI data is disabled by "
> "%select{-fno-rtti-data|/GR-}0">, InGroup<RTTI>;
> def warn_no_typeid_with_rtti_disabled: Warning<
> "typeid will not work since RTTI data is disabled by "
> @@ -7625,8 +7625,7 @@ def warn_condition_is_assignment : Warning<"using the result of an "
> InGroup<Parentheses>;
> def warn_free_nonheap_object
> : Warning<"attempt to call %0 on non-heap object %1">,
> - InGroup<DiagGroup<"free-nonheap-object">>,
> - DefaultIgnore; // FIXME: add to -Wall after sufficient testing
> + InGroup<FreeNonHeapObject>;
>
> // Completely identical except off by default.
> def warn_condition_is_idiomatic_assignment : Warning<"using the result "
>
> diff --git a/clang/test/Analysis/NewDelete-intersections.mm b/clang/test/Analysis/NewDelete-intersections.mm
> index f01d62f8d365..6f81034ee349 100644
> --- a/clang/test/Analysis/NewDelete-intersections.mm
> +++ b/clang/test/Analysis/NewDelete-intersections.mm
> @@ -24,9 +24,6 @@
> extern "C" void free(void *);
>
> void testMallocFreeNoWarn() {
> - int i;
> - free(&i); // no warn
> -
> int *p1 = (int *)malloc(sizeof(int));
> free(++p1); // no warn
>
> @@ -51,7 +48,7 @@ void testDeleteMalloced() {
>
> int *p2 = (int *)__builtin_alloca(sizeof(int));
> delete p2; // no warn
> -}
> +}
>
> void testUseZeroAllocatedMalloced() {
> int *p1 = (int *)malloc(0);
> @@ -79,13 +76,13 @@ void testObjcFreeNewed() {
> }
>
> void testFreeAfterDelete() {
> - int *p = new int;
> + int *p = new int;
> delete p;
> free(p); // newdelete-warning{{Use of memory after it is freed}}
> }
>
> void testStandardPlacementNewAfterDelete() {
> - int *p = new int;
> + int *p = new int;
> delete p;
> p = new (p) int; // newdelete-warning{{Use of memory after it is freed}}
> }
>
> diff --git a/clang/test/Analysis/free.c b/clang/test/Analysis/free.c
> index 0d29bacf274c..b50145713924 100644
> --- a/clang/test/Analysis/free.c
> +++ b/clang/test/Analysis/free.c
> @@ -12,17 +12,23 @@ void *alloca(size_t);
>
> void t1 () {
> int a[] = { 1 };
> - free(a); // expected-warning {{Argument to free() is the address of the local variable 'a', which is not memory allocated by malloc()}}
> + free(a);
> + // expected-warning at -1{{Argument to free() is the address of the local variable 'a', which is not memory allocated by malloc()}}
> + // expected-warning at -2{{attempt to call free on non-heap object 'a'}}
> }
>
> void t2 () {
> int a = 1;
> - free(&a); // expected-warning {{Argument to free() is the address of the local variable 'a', which is not memory allocated by malloc()}}
> + free(&a);
> + // expected-warning at -1{{Argument to free() is the address of the local variable 'a', which is not memory allocated by malloc()}}
> + // expected-warning at -2{{attempt to call free on non-heap object 'a'}}
> }
>
> void t3 () {
> static int a[] = { 1 };
> - free(a); // expected-warning {{Argument to free() is the address of the static variable 'a', which is not memory allocated by malloc()}}
> + free(a);
> + // expected-warning at -1{{Argument to free() is the address of the static variable 'a', which is not memory allocated by malloc()}}
> + // expected-warning at -2{{attempt to call free on non-heap object 'a'}}
> }
>
> void t4 (char *x) {
> @@ -71,12 +77,16 @@ void t13 () {
> }
>
> void t14 (char a) {
> - free(&a); // expected-warning {{Argument to free() is the address of the parameter 'a', which is not memory allocated by malloc()}}
> + free(&a);
> + // expected-warning at -1{{Argument to free() is the address of the parameter 'a', which is not memory allocated by malloc()}}
> + // expected-warning at -2{{attempt to call free on non-heap object 'a'}}
> }
>
> static int someGlobal[2];
> void t15 () {
> - free(someGlobal); // expected-warning {{Argument to free() is the address of the global variable 'someGlobal', which is not memory allocated by malloc()}}
> + free(someGlobal);
> + // expected-warning at -1{{Argument to free() is the address of the global variable 'someGlobal', which is not memory allocated by malloc()}}
> + // expected-warning at -2{{attempt to call free on non-heap object 'someGlobal'}}
> }
>
> void t16 (char **x, int offset) {
>
>
>
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