On Wed, Jan 3, 2024 at 11:22 AM Gregory Nutt <spudan...@gmail.com> wrote: > > On 1/3/2024 10:11 AM, Fotis Panagiotopoulos wrote: > >> That would seem a little odd since there was a PR a few years ago to > > change all instances of assert/ASSERT to DEBUGASSERT to save code size. > > > > How is that so? > > > > As I see here: > > https://github.com/apache/nuttx/blob/master/include/assert.h#L122 > > assert defined exactly as DEBUGASSERT. > > > > There shouldn't be any code size difference at all. > > When CONFIG_DEBUG_ASSERTIONS is not defined, then all occurrences of > DEBUGASSERT compile to nothing (actually the current version compiles to > an expression that is optimized out): > > #undef DEBUGASSERT /* Like ASSERT, but only if > CONFIG_DEBUG_ASSERTIONS is defined */ > > #ifdef CONFIG_DEBUG_ASSERTIONS > # define DEBUGASSERT(f) _ASSERT(f, __DEBUG_ASSERT_FILE__, > __DEBUG_ASSERT_LINE__) > #else > # define DEBUGASSERT(f) ((void)(1 || (f))) > #endif > > This value, ((void)(1 || (f))), is completely removed by the optimizer > because of short-circuiting and dead code removal. So the code is much > smaller if CONFIG_DEBUG_ASSERTIONS is not enabled. If DEBUGASSERT() is > replaced with assert() than that code bloat would be unconditional, > although somewhat less than when assertions are enabled. > > This same kind of logic also applies to DEBUGPANIC and DEBUGVERIFY. > > Xiao Xiang made that change to reduce the size as needed by their > products. He is the person you should be talking to.
Maybe we need NX_DEBUGASSERT, NX_DEBUGPANIC, NX_DEBUGVERIFY. The NX prefix would make it more clear that this is NuttX-specific. These would be used in the OS only, not in applications, and CONFIG_DEBUG_ASSERTIONS would continue to control if these are real or optimized out. Applications that need their own specific, Kconfig-controlled debug assertion, should define one themselves, and their own Kconfig to optimize it out. Rationale: If you are debugging an application, enable assertions only in that application, not everywhere throughout the system. Cheers Nathan
