I am trying to install emacs 27.2 from source on Ubuntu 21.10: $ gcc --version gcc (Ubuntu 11.2.0-7ubuntu2) 11.2.0 $ wget http://ftp.gnu.org/gnu/emacs/emacs-27.2.tar.gz $ tar zvxf emacs-27.2.tar.gz $ cd emacs-27.2 $ ./configure --prefix=/opt/emacs27.2 $ make make -C lib all make[1]: Entering directory '/home/hakon/test/install_emacs/emacs-27.2/lib' GEN alloca.h GEN dirent.h GEN fcntl.h GEN inttypes.h GEN limits.h GEN signal.h GEN stdio.h GEN stdlib.h GEN string.h GEN sys/select.h GEN sys/stat.h GEN sys/time.h GEN sys/types.h GEN time.h GEN unistd.h CC fingerprint.o CC fcntl.o CC fsusage.o CC regex.o CC sig2str.o CC time_rz.o CC acl-errno-valid.o CC acl-internal.o CC get-permissions.o CC set-permissions.o CC allocator.o CC binary-io.o CC c-ctype.o CC c-strcasecmp.o CC c-strncasecmp.o CC careadlinkat.o careadlinkat.c: In function ‘careadlinkat’: cc1: warning: function may return address of local variable [-Wreturn-local-addr] careadlinkat.c:73:8: note: declared here 73 | char stack_buf[1024]; | ^~~~~~~~~ CC close-stream.o CC count-leading-zeros.o CC count-one-bits.o CC count-trailing-zeros.o CC md5.o CC sha1.o CC sha256.o CC sha512.o CC dtoastr.o CC dtotimespec.o CC filemode.o CC filevercmp.o CC gettime.o CC nstrftime.o CC pipe2.o CC qcopy-acl.o CC stat-time.o CC tempname.o CC timespec.o CC timespec-add.o CC timespec-sub.o CC u64.o CC unistd.o CC utimens.o utimens.c: In function ‘fdutimens’: utimens.c:382:17: warning: ‘update_timespec’ accessing 16 bytes in a region of size 8 [-Wstringop-overflow=] 382 | if (ts && update_timespec (&st, &ts)) | ^~~~~~~~~~~~~~~~~~~~~~~~~~ utimens.c:382:17: note: referencing argument 2 of type ‘struct timespec **’ utimens.c:133:1: note: in a call to function ‘update_timespec’ 133 | update_timespec (struct stat const *statbuf, struct timespec *ts[2]) | ^~~~~~~~~~~~~~~ utimens.c: In function ‘lutimens’: utimens.c:595:17: warning: ‘update_timespec’ accessing 16 bytes in a region of size 8 [-Wstringop-overflow=] 595 | if (ts && update_timespec (&st, &ts)) | ^~~~~~~~~~~~~~~~~~~~~~~~~~ utimens.c:595:17: note: referencing argument 2 of type ‘struct timespec **’ utimens.c:133:1: note: in a call to function ‘update_timespec’ 133 | update_timespec (struct stat const *statbuf, struct timespec *ts[2]) | ^~~~~~~~~~~~~~~ CC openat-die.o CC save-cwd.o AR libgnu.a make[1]: Leaving directory '/home/hakon/test/install_emacs/emacs-27.2/lib' make -C lib-src all make[1]: Entering directory '/home/hakon/test/install_emacs/emacs-27.2/lib-src' CCLD etags CCLD ctags etags.c: In function ‘main’: cc1: warning: ‘__builtin_memcpy’ writing 12 bytes into a region of size between 0 and 7 [-Wstringop-overflow=] In file included from ctags.c:2: etags.c:1395:21: note: destination object of size [0, 7] allocated by ‘xmalloc’ 1395 | char *cmd = xmalloc (2 * strlen (tagfile) + sizeof "sort -u -o.."); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ etags.c:1401:14: warning: writing 1 byte into a region of size 0 [-Wstringop-overflow=] 1401 | *z++ = ' '; | ~~~~~^~~~~ etags.c:1395:21: note: at offset 11 into destination object of size [0, 7] allocated by ‘xmalloc’ 1395 | char *cmd = xmalloc (2 * strlen (tagfile) + sizeof "sort -u -o.."); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ In file included from /usr/include/string.h:519, from ../lib/string.h:41, from etags.c:120, from ctags.c:2: In function ‘stpcpy’, inlined from ‘main’ at etags.c:1400:6: /usr/include/x86_64-linux-gnu/bits/string_fortified.h:86:10: warning: ‘__builtin_stpcpy’ writing 1 or more bytes into a region of size 0 overflows the destination [-Wstringop-overflow=] 86 | return __builtin___stpcpy_chk (__dest, __src, __glibc_objsize (__dest)); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ In file included from ctags.c:2: /usr/include/x86_64-linux-gnu/bits/string_fortified.h: In function ‘main’: etags.c:1395:21: note: at offset 11 into destination object of size [0, 7] allocated by ‘xmalloc’ 1395 | char *cmd = xmalloc (2 * strlen (tagfile) + sizeof "sort -u -o.."); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ In file included from /usr/include/string.h:519, from ../lib/string.h:41, from etags.c:120, from ctags.c:2: In function ‘strcpy’, inlined from ‘main’ at etags.c:1402:2: /usr/include/x86_64-linux-gnu/bits/string_fortified.h:79:10: warning: ‘__builtin_strcpy’ writing 1 or more bytes into a region of size 0 overflows the destination [-Wstringop-overflow=] 79 | return __builtin___strcpy_chk (__dest, __src, __glibc_objsize (__dest)); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ In file included from ctags.c:2: /usr/include/x86_64-linux-gnu/bits/string_fortified.h: In function ‘main’: etags.c:1395:21: note: at offset 12 into destination object of size [0, 7] allocated by ‘xmalloc’ 1395 | char *cmd = xmalloc (2 * strlen (tagfile) + sizeof "sort -u -o.."); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ CCLD emacsclient CCLD ebrowse CCLD hexl CC pop.o CCLD movemail CCLD make-docfile CCLD make-fingerprint make[1]: Leaving directory '/home/hakon/test/install_emacs/emacs-27.2/lib-src' make -C src VCSWITNESS='' all make[1]: Entering directory '/home/hakon/test/install_emacs/emacs-27.2/src' GEN lisp.mk GEN globals.h CC dispnew.o CC frame.o CC scroll.o CC xdisp.o CC menu.o CC xmenu.o CC window.o CC charset.o CC coding.o CC category.o CC ccl.o CC character.o CC chartab.o CC bidi.o CC cm.o CC term.o CC terminal.o CC xfaces.o CC xterm.o CC xfns.o CC xselect.o CC xrdb.o CC xsmfns.o CC xsettings.o CC gtkutil.o CC emacsgtkfixed.o CC dbusbind.o CC emacs.o CC keyboard.o CC macros.o CC keymap.o CC sysdep.o sysdep.c:1821:22: error: variably modified ‘sigsegv_stack’ at file scope 1821 | static unsigned char sigsegv_stack[SIGSTKSZ]; | ^~~~~~~~~~~~~ make[1]: *** [Makefile:406: sysdep.o] Error 1 make[1]: Leaving directory '/home/hakon/test/install_emacs/emacs-27.2/src' make: *** [Makefile:424: src] Error 2