On Mon, 17 Nov 2025 14:14:03 +0100,
Claudio Jeker <cjeker@diehard.n-r-g.com> wrote:
> 
> In gcc -fdelete-null-pointer-checks is a nightmare.
> 
> It is a stupid optimisation which has some bad security track record since
> it tends to remove 'if (p == NULL) error out' checks. Now on OpenBSD you can
> not map the page at address 0 so it is less of a concern since in that
> case the code should crash before the check (at least that is the theory).
> 
> The problem with skipping this optimisation is that a lot of c++ code
> breaks because of static asserts against nullptr.
> Many of those expressions are actually not using proper const expressions
> and so gcc errors out. With -fdelete-null-pointer-checks these checks
> get optimised away (because the compiler decided that somewhen before the
> static assert the pointer was already dereferenced and so impossible to be
> NULL).
> 
> I got tired to figure out how to pass -fdelete-null-pointer-checks to all
> those c++ monsters. The common linux distros all ship with a gcc that has
> -fdelete-null-pointer-checks set by default and so we just inflict a lot
> of pain on us for being a special snowflake.
>

OK kirill@

> -- 
> :wq Claudio
> 
> Index: Makefile
> ===================================================================
> RCS file: /cvs/ports/lang/gcc/15/Makefile,v
> diff -u -p -r1.13 Makefile
> --- Makefile	13 Nov 2025 23:30:14 -0000	1.13
> +++ Makefile	17 Nov 2025 12:57:04 -0000
> @@ -18,7 +18,7 @@ V = 15.2.0
>  FULL_VERSION = $V
>  FULL_PKGVERSION = $V
>  
> -REVISION = 3
> +REVISION = 4
>  
>  ADASTRAP-amd64 = adastrap-amd64-11.2.0-5.tar.xz
>  ADASTRAP-arm = adastrap-arm-4.9.4-0.tar.xz
> Index: patches/patch-gcc_common_opt
> ===================================================================
> RCS file: /cvs/ports/lang/gcc/15/patches/patch-gcc_common_opt,v
> diff -u -p -r1.1.1.1 patch-gcc_common_opt
> --- patches/patch-gcc_common_opt	18 Aug 2025 19:49:22 -0000	1.1.1.1
> +++ patches/patch-gcc_common_opt	12 Nov 2025 12:57:16 -0000
> @@ -41,15 +41,6 @@ Index: gcc/common.opt
>   Aggressively optimize loops using language constraints.
>   
>   falign-functions
> -@@ -1359,7 +1367,7 @@ Common Var(flag_delete_dead_exceptions) Init(0) Optimi
> - Delete dead instructions that may throw exceptions.
> - 
> - fdelete-null-pointer-checks
> --Common Var(flag_delete_null_pointer_checks) Init(-1) Optimization
> -+Common Var(flag_delete_null_pointer_checks) Init(0) Optimization
> - Delete useless null pointer checks.
> - 
> - fdevirtualize-at-ltrans
>  @@ -1943,7 +1951,7 @@ Enum(hardcfr_check_noreturn_calls) String(always) Valu
>   ; On SVR4 targets, it also controls whether or not to emit a
>   ; string identifying the compiler.
> 

-- 
wbr, Kirill