[Bug middle-end/77784] duplicate warning for snprintf when n > object size
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77784 Martin Sebor changed: What|Removed |Added Status|ASSIGNED|RESOLVED See Also||https://gcc.gnu.org/bugzill ||a/show_bug.cgi?id=78138 Resolution|--- |FIXED --- Comment #4 from Martin Sebor --- Fixed in r243419.
[Bug middle-end/77784] duplicate warning for snprintf when n > object size
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77784 --- Comment #3 from Martin Sebor --- Author: msebor Date: Thu Dec 8 00:01:33 2016 New Revision: 243419 URL: https://gcc.gnu.org/viewcvs?rev=243419&root=gcc&view=rev Log: PR c/53562 - Add -Werror= support for -D_FORTIFY_SOURCE / __builtin___memcpy_chk PR middle-end/77784 - duplicate warning for snprintf when n > object size PR middle-end/78149 - missing warning on strncpy buffer overflow due to an excessive bound PR middle-end/78138 - missing warnings on buffer overflow with non-constant source length gcc/c-family/ChangeLog: PR c/53562 PR middle-end/77784 PR middle-end/78149 PR middle-end/78138 * c.opt (-Wstringop-overflow): New option. gcc/ChangeLog: PR middle-end/77784 PR middle-end/78149 PR middle-end/78138 * builtins.c (expand_builtin_strcat, expand_builtin_strncat): New functions. (compute_dest_size, get_size_range, check_sizes, check_strncat_sizes) (check_memop_sizes): Same. (expand_builtin_memcpy): Call check memop_sizes. (expand_builtin_mempcpy): Same. (expand_builtin_memset): Same, (expand_builtin_bzero): Same. (expand_builtin_memory_chk): Call check_sizes. (expand_builtin_strcpy): Same. (expand_builtin_strncpy): Same. (maybe_emit_sprintf_chk_warning): Same. (expand_builtin): Handle strcat and strncat. (fini_object_sizes): Reset pointers. (compute_object_size): New function. * gimple-ssa-sprintf.c (pass_sprintf_length::handle_gimple_call): Avoid issuing warnings also issued during built-in expansion. * doc/invoke.texi (Warning Options): Document -Wstringop-overflow. gcc/testsuite/ChangeLog: PR middle-end/77784 PR middle-end/78149 PR middle-end/78138 * c-c++-common/Wsizeof-pointer-memaccess2.c: Adjust expected diagnostic. * g++.dg/ext/builtin-object-size3.C (bar): Same. * g++.dg/ext/strncpy-chk1.C: Same. * g++.dg/opt/memcpy1.C: Same. * g++.dg/torture/Wsizeof-pointer-memaccess1.C: Same. * gcc.c-torture/compile/pr55569.c: Disable -Wstringop-overflow. * gcc.dg/Wobjsize-1.c: Adjust expected diagnostic. * gcc.dg/attr-alloc_size.c: Same. * gcc.dg/builtin-stringop-chk-1.c: Adjust expected diagnostic. * gcc.dg/builtin-stringop-chk-2.c: Same. * gcc.dg/builtin-stringop-chk-4.c: New test. * gcc.dg/builtin-strncat-chk-1.c: Adjust expected diagnostic. * gcc.dg/memcpy-2.c: Same. * gcc.dg/pr40340-1.c: Same. * gcc.dg/pr40340-2.c (main): Same. * gcc.dg/pr40340-5.c (main): Same. * gcc.dg/torture/Wsizeof-pointer-memaccess1.c: Same. * gcc.dg/torture/pr71132.c: Disable -Wstringop-overflow. * gcc.dg/tree-ssa/builtin-sprintf-warn-1.c: Adjust text of expected warning. * gfortran.dg/char_length_3.f90: Prune expected warnings. * gfortran.dg/pr38868.f: Add expected warnings. Added: trunk/gcc/testsuite/gcc.dg/builtin-stringop-chk-4.c trunk/gcc/testsuite/gcc.dg/builtin-stringop-chk-5.c trunk/gcc/testsuite/gcc.dg/builtin-stringop-chk-6.c Modified: trunk/gcc/ChangeLog trunk/gcc/builtins.c trunk/gcc/c-family/ChangeLog trunk/gcc/c-family/c.opt trunk/gcc/doc/invoke.texi trunk/gcc/gimple-ssa-sprintf.c trunk/gcc/testsuite/ChangeLog trunk/gcc/testsuite/c-c++-common/Wsizeof-pointer-memaccess2.c trunk/gcc/testsuite/g++.dg/ext/builtin-object-size3.C trunk/gcc/testsuite/g++.dg/ext/strncpy-chk1.C trunk/gcc/testsuite/g++.dg/opt/memcpy1.C trunk/gcc/testsuite/g++.dg/torture/Wsizeof-pointer-memaccess1.C trunk/gcc/testsuite/g++.dg/torture/Wsizeof-pointer-memaccess2.C trunk/gcc/testsuite/gcc.c-torture/compile/pr55569.c trunk/gcc/testsuite/gcc.dg/Wobjsize-1.c trunk/gcc/testsuite/gcc.dg/attr-alloc_size.c trunk/gcc/testsuite/gcc.dg/builtin-stringop-chk-1.c trunk/gcc/testsuite/gcc.dg/builtin-stringop-chk-2.c trunk/gcc/testsuite/gcc.dg/builtin-strncat-chk-1.c trunk/gcc/testsuite/gcc.dg/fstack-protector-strong.c trunk/gcc/testsuite/gcc.dg/memcpy-2.c trunk/gcc/testsuite/gcc.dg/pr40340-1.c trunk/gcc/testsuite/gcc.dg/pr40340-2.c trunk/gcc/testsuite/gcc.dg/pr40340-5.c trunk/gcc/testsuite/gcc.dg/torture/Wsizeof-pointer-memaccess1.c trunk/gcc/testsuite/gcc.dg/torture/pr71132.c trunk/gcc/testsuite/gcc.dg/tree-ssa/builtin-sprintf-warn-1.c trunk/gcc/testsuite/gcc.dg/tree-ssa/builtin-sprintf-warn-3.c trunk/gcc/testsuite/gfortran.dg/char_length_3.f90 trunk/gcc/testsuite/gfortran.dg/pr38868.f
[Bug middle-end/77784] duplicate warning for snprintf when n > object size
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77784 Martin Sebor changed: What|Removed |Added Status|NEW |ASSIGNED Assignee|unassigned at gcc dot gnu.org |msebor at gcc dot gnu.org --- Comment #2 from Martin Sebor --- I'll handle this in an update on my cumulative patch for bug 53562 initially posted for review here: https://gcc.gnu.org/ml/gcc-patches/2016-10/msg02308.html
[Bug middle-end/77784] duplicate warning for snprintf when n > object size
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77784 Jakub Jelinek changed: What|Removed |Added CC||jakub at gcc dot gnu.org --- Comment #1 from Jakub Jelinek --- The preexisting warning is not that misleading, because even if there is not any buffer overflow, the program is still terminated whenever the user provided buffer size is bigger than the __builtin_object_size provided size, without actually trying to print anything into the buffer. If you want to suggest different wording for the *snprintf* case, it could be changed, but I believe it is the right spot for the warning - after all the GIMPLE optimizations, regardless of what warning options are enabled or not.
[Bug middle-end/77784] duplicate warning for snprintf when n > object size
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77784 Martin Sebor changed: What|Removed |Added Keywords||diagnostic Status|UNCONFIRMED |NEW Last reconfirmed||2016-09-28 Summary|duplicate warning for |duplicate warning for |snprintf for n > object |snprintf when n > object |size|size Ever confirmed|0 |1 Severity|normal |minor
