From e921f97df9a11fd6f43ee040ba97c686c3fa62ee Mon Sep 17 00:00:00 2001 From: Paul Eggert Date: Tue, 12 Dec 2017 12:59:27 -0800 Subject: [PATCH] Port --fcheck-pointer-bounds to --with-wide-int * src/lisp (XSYMBOL) [__CHKP__ && !USE_LSB_TAG]: Bypass pointer bounds checking here, instead of failing the entire build. (make_lisp_symbol): Improve comment. --- src/lisp.h | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/src/lisp.h b/src/lisp.h index 56545b70946..eb31ba209a6 100644 --- a/src/lisp.h +++ b/src/lisp.h @@ -902,12 +902,15 @@ INLINE struct Lisp_Symbol * { #if USE_LSB_TAG return lisp_h_XSYMBOL (a); -#elif defined __CHKP__ -# error "pointer-checking not supported with wide integers" #else eassert (SYMBOLP (a)); intptr_t i = (intptr_t) XUNTAG (a, Lisp_Symbol); void *p = (char *) lispsym + i; +# ifdef __CHKP__ + /* Bypass pointer checking. Although this could be improved it is + probably not worth the trouble. */ + p = __builtin___bnd_set_ptr_bounds (p, sizeof (struct Lisp_Symbol)); +# endif return p; #endif } @@ -916,9 +919,11 @@ INLINE Lisp_Object make_lisp_symbol (struct Lisp_Symbol *sym) { #ifdef __CHKP__ - /* Although this should use '__builtin___bnd_narrow_ptr_bounds (sym, - sym, sizeof *sym)', that would run afoul of GCC bug 83251 - . */ + /* Although '__builtin___bnd_narrow_ptr_bounds (sym, sym, sizeof *sym)' + should be more efficient, it runs afoul of GCC bug 83251 + . + Also, attempting to call __builtin___bnd_chk_ptr_bounds (sym, sizeof *sym) + here seems to trigger a GCC bug, as yet undiagnosed. */ char *addr = __builtin___bnd_set_ptr_bounds (sym, sizeof *sym); char *symoffset = addr - (intptr_t) lispsym; #else -- 2.39.2