1 sinclude(../config/acx.m4) 2 sinclude(../config/no-executables.m4) 3 sinclude(../config/override.m4) 4 sinclude(../config/picflag.m4) 5 sinclude(../config/warnings.m4) 6 7 dnl See whether strncmp reads past the end of its string parameters. 8 dnl On some versions of SunOS4 at least, strncmp reads a word at a time 9 dnl but erroneously reads past the end of strings. This can cause 10 dnl a SEGV in some cases. 11 AC_DEFUN(libiberty_AC_FUNC_STRNCMP, 12 [AC_REQUIRE([AC_FUNC_MMAP]) 13 AC_CACHE_CHECK([for working strncmp], ac_cv_func_strncmp_works, 14 [AC_TRY_RUN([ 15 /* Test by Jim Wilson and Kaveh Ghazi. 16 Check whether strncmp reads past the end of its string parameters. */ 17 #include <sys/types.h> 18 19 #ifdef HAVE_FCNTL_H 20 #include <fcntl.h> 21 #endif 22 23 #ifdef HAVE_SYS_MMAN_H 24 #include <sys/mman.h> 25 #endif 26 27 #ifndef MAP_ANON 28 #ifdef MAP_ANONYMOUS 29 #define MAP_ANON MAP_ANONYMOUS 30 #else 31 #define MAP_ANON MAP_FILE 32 #endif 33 #endif 34 35 #ifndef MAP_FILE 36 #define MAP_FILE 0 37 #endif 38 #ifndef O_RDONLY 39 #define O_RDONLY 0 40 #endif 41 42 #define MAP_LEN 0x10000 43 44 main () 45 { 46 #if defined(HAVE_MMAP) || defined(HAVE_MMAP_ANYWHERE) 47 char *p; 48 int dev_zero; 49 50 dev_zero = open ("/dev/zero", O_RDONLY); 51 if (dev_zero < 0) 52 exit (1); 53 54 p = (char *) mmap (0, MAP_LEN, PROT_READ|PROT_WRITE, 55 MAP_ANON|MAP_PRIVATE, dev_zero, 0); 56 if (p == (char *)-1) 57 p = (char *) mmap (0, MAP_LEN, PROT_READ|PROT_WRITE, 58 MAP_ANON|MAP_PRIVATE, -1, 0); 59 if (p == (char *)-1) 60 exit (2); 61 else 62 { 63 char *string = "__si_type_info"; 64 char *q = (char *) p + MAP_LEN - strlen (string) - 2; 65 char *r = (char *) p + 0xe; 66 67 strcpy (q, string); 68 strcpy (r, string); 69 strncmp (r, q, 14); 70 } 71 #endif /* HAVE_MMAP || HAVE_MMAP_ANYWHERE */ 72 exit (0); 73 } 74 ], ac_cv_func_strncmp_works=yes, ac_cv_func_strncmp_works=no, 75 ac_cv_func_strncmp_works=yes) 76 rm -f core core.* *.core]) 77 if test $ac_cv_func_strncmp_works = no ; then 78 AC_LIBOBJ([strncmp]) 79 fi 80 ]) 81 82 dnl See if errno must be declared even when <errno.h> is included. 83 AC_DEFUN(libiberty_AC_DECLARE_ERRNO, 84 [AC_CACHE_CHECK(whether errno must be declared, libiberty_cv_declare_errno, 85 [AC_TRY_COMPILE( 86 [#include <errno.h>], 87 [int x = errno;], 88 libiberty_cv_declare_errno=no, 89 libiberty_cv_declare_errno=yes)]) 90 if test $libiberty_cv_declare_errno = yes 91 then AC_DEFINE(NEED_DECLARATION_ERRNO, 1, 92 [Define if errno must be declared even when <errno.h> is included.]) 93 fi 94 ]) 95 96 dnl See whether we need a declaration for a function. 97 AC_DEFUN(libiberty_NEED_DECLARATION, 98 [AC_MSG_CHECKING([whether $1 must be declared]) 99 AC_CACHE_VAL(libiberty_cv_decl_needed_$1, 100 [AC_TRY_COMPILE([ 101 #include "confdefs.h" 102 #include <stdio.h> 103 #ifdef HAVE_STRING_H 104 #include <string.h> 105 #else 106 #ifdef HAVE_STRINGS_H 107 #include <strings.h> 108 #endif 109 #endif 110 #ifdef HAVE_STDLIB_H 111 #include <stdlib.h> 112 #endif 113 #ifdef HAVE_UNISTD_H 114 #include <unistd.h> 115 #endif], 116 [char *(*pfn) = (char *(*)) $1], 117 libiberty_cv_decl_needed_$1=no, libiberty_cv_decl_needed_$1=yes)]) 118 AC_MSG_RESULT($libiberty_cv_decl_needed_$1) 119 if test $libiberty_cv_decl_needed_$1 = yes; then 120 AC_DEFINE([NEED_DECLARATION_]translit($1, [a-z], [A-Z]), 1, 121 [Define if $1 is not declared in system header files.]) 122 fi 123 ])dnl 124 125 # We always want a C version of alloca() compiled into libiberty, 126 # because native-compiler support for the real alloca is so !@#$% 127 # unreliable that GCC has decided to use it only when being compiled 128 # by GCC. This is the part of AC_FUNC_ALLOCA that calculates the 129 # information alloca.c needs. 130 AC_DEFUN(libiberty_AC_FUNC_C_ALLOCA, 131 [AC_CACHE_CHECK(whether alloca needs Cray hooks, ac_cv_os_cray, 132 [AC_EGREP_CPP(webecray, 133 [#if defined(CRAY) && ! defined(CRAY2) 134 webecray 135 #else 136 wenotbecray 137 #endif 138 ], ac_cv_os_cray=yes, ac_cv_os_cray=no)]) 139 if test $ac_cv_os_cray = yes; then 140 for ac_func in _getb67 GETB67 getb67; do 141 AC_CHECK_FUNC($ac_func, 142 [AC_DEFINE_UNQUOTED(CRAY_STACKSEG_END, $ac_func, 143 [Define to one of _getb67, GETB67, getb67 for Cray-2 and Cray-YMP 144 systems. This function is required for alloca.c support on those 145 systems.]) break]) 146 done 147 fi 148 149 AC_CACHE_CHECK(stack direction for C alloca, ac_cv_c_stack_direction, 150 [AC_TRY_RUN([find_stack_direction () 151 { 152 static char *addr = 0; 153 auto char dummy; 154 if (addr == 0) 155 { 156 addr = &dummy; 157 return find_stack_direction (); 158 } 159 else 160 return (&dummy > addr) ? 1 : -1; 161 } 162 main () 163 { 164 exit (find_stack_direction() < 0); 165 }], 166 ac_cv_c_stack_direction=1, 167 ac_cv_c_stack_direction=-1, 168 ac_cv_c_stack_direction=0)]) 169 AC_DEFINE_UNQUOTED(STACK_DIRECTION, $ac_cv_c_stack_direction, 170 [Define if you know the direction of stack growth for your system; 171 otherwise it will be automatically deduced at run-time. 172 STACK_DIRECTION > 0 => grows toward higher addresses 173 STACK_DIRECTION < 0 => grows toward lower addresses 174 STACK_DIRECTION = 0 => direction of growth unknown]) 175 ]) 176
