From: Siddhesh Poyarekar Date: Thu, 22 Jul 2021 13:07:57 +0000 (+0530) Subject: Remove __morecore and __default_morecore X-Git-Tag: glibc-2.34~33 X-Git-Url: https://sourceware.org/git/?a=commitdiff_plain;h=55a4dd39308951da4b0da84b19e415c2bb451b60;p=glibc.git Remove __morecore and __default_morecore Make the __morecore and __default_morecore symbols compat-only and remove their declarations from the API. Also, include morecore.c directly into malloc.c; this should ideally get merged into malloc in a future cleanup. Reviewed-by: Carlos O'Donell Tested-by: Carlos O'Donell --- diff --git a/NEWS b/NEWS index 4df348cce5..75ad8a9b95 100644 --- a/NEWS +++ b/NEWS @@ -127,6 +127,11 @@ Deprecated and removed features, and other changes affecting compatibility: mtrace. Similar functionality can be achieved by using conditional breakpoints within mtrace functions from within gdb. +* The __morecore and __after_morecore_hook malloc hooks and the default + implementation __default_morecore have been removed from the API. Existing + applications will continue to link against these symbols but the interfaces + no longer have any effect on malloc. + Changes to build and runtime requirements: * On Linux, the shm_open, sem_open, and related functions now expect the diff --git a/include/stdlib.h b/include/stdlib.h index 1f6e1508e4..1c6f70b082 100644 --- a/include/stdlib.h +++ b/include/stdlib.h @@ -306,9 +306,6 @@ libc_hidden_proto (__qfcvt_r) # define MB_CUR_MAX (_NL_CURRENT_WORD (LC_CTYPE, _NL_CTYPE_MB_CUR_MAX)) # endif -extern void *__default_morecore (ptrdiff_t) __THROW; -libc_hidden_proto (__default_morecore) - struct abort_msg_s { unsigned int size; diff --git a/malloc/Makefile b/malloc/Makefile index 063d103d97..bbb70f6f87 100644 --- a/malloc/Makefile +++ b/malloc/Makefile @@ -104,7 +104,7 @@ tests-exclude-mcheck = tst-mallocstate \ tests-mcheck = $(filter-out $(tests-exclude-mcheck), $(tests)) endif -routines = malloc morecore mcheck mtrace obstack reallocarray \ +routines = malloc mcheck mtrace obstack reallocarray \ scratch_buffer_dupfree \ scratch_buffer_grow scratch_buffer_grow_preserve \ scratch_buffer_set_array_size \ diff --git a/malloc/arena.c b/malloc/arena.c index 991fc21a7e..f1693ed48f 100644 --- a/malloc/arena.c +++ b/malloc/arena.c @@ -274,14 +274,6 @@ next_env_entry (char ***position) #endif -#if defined(SHARED) || defined(USE_MTAG) -static void * -__failing_morecore (ptrdiff_t d) -{ - return (void *) MORECORE_FAILURE; -} -#endif - #ifdef SHARED extern struct dl_open_hook *_dl_open_hook; libc_hidden_proto (_dl_open_hook); @@ -310,7 +302,7 @@ ptmalloc_init (void) and that morecore does not support tagged regions, then disable it. */ if (__MTAG_SBRK_UNTAGGED) - __morecore = __failing_morecore; + __always_fail_morecore = true; mtag_enabled = true; mtag_mmap_flags = __MTAG_MMAP_FLAGS; @@ -323,7 +315,7 @@ ptmalloc_init (void) generic sbrk implementation also enforces this, but it is not used on Hurd. */ if (!__libc_initial) - __morecore = __failing_morecore; + __always_fail_morecore = true; #endif thread_arena = &main_arena; diff --git a/malloc/hooks.c b/malloc/hooks.c index 45c91d6502..4aa6dadcff 100644 --- a/malloc/hooks.c +++ b/malloc/hooks.c @@ -20,6 +20,8 @@ #if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_34) void weak_variable (*__after_morecore_hook) (void) = NULL; compat_symbol (libc, __after_morecore_hook, __after_morecore_hook, GLIBC_2_0); +void *(*__morecore)(ptrdiff_t); +compat_symbol (libc, __morecore, __morecore, GLIBC_2_0); #endif /* Hooks for debugging versions. The initial hooks just call the diff --git a/malloc/malloc.c b/malloc/malloc.c index 24e7854a0e..6e8fa9e424 100644 --- a/malloc/malloc.c +++ b/malloc/malloc.c @@ -384,12 +384,11 @@ __malloc_assert (const char *assertion, const char *file, unsigned int line, #define TRIM_FASTBINS 0 #endif - /* Definition for getting more memory from the OS. */ -#define MORECORE (*__morecore) +#include "morecore.c" + +#define MORECORE (*__glibc_morecore) #define MORECORE_FAILURE 0 -void * __default_morecore (ptrdiff_t); -void *(*__morecore)(ptrdiff_t) = __default_morecore; /* Memory tagging. */ diff --git a/malloc/malloc.h b/malloc/malloc.h index 634b7db868..17ab9ee345 100644 --- a/malloc/malloc.h +++ b/malloc/malloc.h @@ -76,14 +76,6 @@ extern void *valloc (size_t __size) __THROW __attribute_malloc__ extern void *pvalloc (size_t __size) __THROW __attribute_malloc__ __wur __attr_dealloc_free; -/* Underlying allocation function; successive calls should return - contiguous pieces of memory. */ -extern void *(*__morecore) (ptrdiff_t __size) __MALLOC_DEPRECATED; - -/* Default value of `__morecore'. */ -extern void *__default_morecore (ptrdiff_t __size) -__THROW __attribute_malloc__ __MALLOC_DEPRECATED; - /* SVID2/XPG mallinfo structure */ struct mallinfo diff --git a/malloc/morecore.c b/malloc/morecore.c index 047228779b..8168ef158c 100644 --- a/malloc/morecore.c +++ b/malloc/morecore.c @@ -15,39 +15,27 @@ License along with the GNU C Library; if not, see . */ -#ifndef _MALLOC_INTERNAL -# define _MALLOC_INTERNAL -# include -#endif - -#ifndef __GNU_LIBRARY__ -# define __sbrk sbrk -#endif - -#ifdef __GNU_LIBRARY__ -/* It is best not to declare this and cast its result on foreign operating - systems with potentially hostile include files. */ - -# include -# include -extern void *__sbrk (ptrdiff_t increment) __THROW; -libc_hidden_proto (__sbrk) -#endif - -#ifndef NULL -# define NULL 0 +#if defined(SHARED) || defined(USE_MTAG) +static bool __always_fail_morecore = false; #endif /* Allocate INCREMENT more bytes of data space, and return the start of data space, or NULL on errors. If INCREMENT is negative, shrink data space. */ void * -__default_morecore (ptrdiff_t increment) +__glibc_morecore (ptrdiff_t increment) { +#if defined(SHARED) || defined(USE_MTAG) + if (__always_fail_morecore) + return NULL; +#endif + void *result = (void *) __sbrk (increment); if (result == (void *) -1) return NULL; return result; } -libc_hidden_def (__default_morecore) +#if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_34) +compat_symbol (libc, __glibc_morecore, __default_morecore, GLIBC_2_0); +#endif