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engine=8.12.0-2210170000 definitions=main-2212060136 X-Proofpoint-ORIG-GUID: LUEJBLdvprjDJXuwXWPsvpNzLN9upyoy X-Proofpoint-GUID: LUEJBLdvprjDJXuwXWPsvpNzLN9upyoy X-Spam-Status: No, score=-11.3 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, RCVD_IN_DNSWL_LOW, RCVD_IN_MSPIKE_H2, SPF_HELO_NONE, SPF_NONE, TXREP autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org X-BeenThere: gcc-patches@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Qing Zhao via Gcc-patches From: Qing Zhao Reply-To: Qing Zhao Errors-To: gcc-patches-bounces+patchwork=sourceware.org@gcc.gnu.org Sender: "Gcc-patches" '-Wstrict-flex-arrays' Warn about inproper usages of flexible array members according to the LEVEL of the 'strict_flex_array (LEVEL)' attribute attached to the trailing array field of a structure if it's available, otherwise according to the LEVEL of the option '-fstrict-flex-arrays=LEVEL'. This option is effective only when LEVEL is bigger than 0. Otherwise, it will be ignored with a warning. when LEVEL=1, warnings will be issued for a trailing array reference of a structure that have 2 or more elements if the trailing array is referenced as a flexible array member. when LEVEL=2, in addition to LEVEL=1, additional warnings will be issued for a trailing one-element array reference of a structure if the array is referenced as a flexible array member. when LEVEL=3, in addition to LEVEL=2, additional warnings will be issued for a trailing zero-length array reference of a structure if the array is referenced as a flexible array member. gcc/ChangeLog: * doc/invoke.texi: Document -Wstrict-flex-arrays option. * gimple-array-bounds.cc (check_out_of_bounds_and_warn): Add two more arguments. (array_bounds_checker::check_array_ref): Issue warnings for -Wstrict-flex-arrays. * opts.cc (finish_options): Issue warning for unsupported combination of -Wstrict_flex_arrays and -fstrict-flex-array. * tree-vrp.cc (execute_ranger_vrp): Enable the pass when warn_strict_flex_array is true. gcc/c-family/ChangeLog: * c.opt (Wstrict-flex-arrays): New option. gcc/testsuite/ChangeLog: * gcc.dg/Warray-bounds-flex-arrays-1.c: Update testing case with -Wstrict-flex-arrays. * gcc.dg/Warray-bounds-flex-arrays-2.c: Likewise. * gcc.dg/Warray-bounds-flex-arrays-3.c: Likewise. * gcc.dg/Warray-bounds-flex-arrays-4.c: Likewise. * gcc.dg/Warray-bounds-flex-arrays-5.c: Likewise. * gcc.dg/Warray-bounds-flex-arrays-6.c: Likewise. * c-c++-common/Wstrict-flex-arrays.c: New test. * gcc.dg/Wstrict-flex-arrays-2.c: New test. * gcc.dg/Wstrict-flex-arrays-3.c: New test. * gcc.dg/Wstrict-flex-arrays.c: New test. --- gcc/c-family/c.opt | 5 + gcc/doc/invoke.texi | 27 ++++- gcc/gimple-array-bounds.cc | 103 ++++++++++++++---- gcc/opts.cc | 8 ++ .../c-c++-common/Wstrict-flex-arrays.c | 9 ++ .../gcc.dg/Warray-bounds-flex-arrays-1.c | 5 +- .../gcc.dg/Warray-bounds-flex-arrays-2.c | 6 +- .../gcc.dg/Warray-bounds-flex-arrays-3.c | 7 +- .../gcc.dg/Warray-bounds-flex-arrays-4.c | 5 +- .../gcc.dg/Warray-bounds-flex-arrays-5.c | 6 +- .../gcc.dg/Warray-bounds-flex-arrays-6.c | 7 +- gcc/testsuite/gcc.dg/Wstrict-flex-arrays-2.c | 39 +++++++ gcc/testsuite/gcc.dg/Wstrict-flex-arrays-3.c | 39 +++++++ gcc/testsuite/gcc.dg/Wstrict-flex-arrays.c | 39 +++++++ gcc/tree-vrp.cc | 2 +- 15 files changed, 273 insertions(+), 34 deletions(-) create mode 100644 gcc/testsuite/c-c++-common/Wstrict-flex-arrays.c create mode 100644 gcc/testsuite/gcc.dg/Wstrict-flex-arrays-2.c create mode 100644 gcc/testsuite/gcc.dg/Wstrict-flex-arrays-3.c create mode 100644 gcc/testsuite/gcc.dg/Wstrict-flex-arrays.c diff --git a/gcc/c-family/c.opt b/gcc/c-family/c.opt index 0d0ad0a6374..33edeefd285 100644 --- a/gcc/c-family/c.opt +++ b/gcc/c-family/c.opt @@ -976,6 +976,11 @@ Wstringop-truncation C ObjC C++ LTO ObjC++ Var(warn_stringop_truncation) Warning Init (1) LangEnabledBy(C ObjC C++ LTO ObjC++, Wall) Warn about truncation in string manipulation functions like strncat and strncpy. +Wstrict-flex-arrays +C C++ Var(warn_strict_flex_arrays) Warning +Warn about inproper usages of flexible array members +according to the level of -fstrict-flex-arrays. + Wsuggest-attribute=format C ObjC C++ ObjC++ Var(warn_suggest_attribute_format) Warning Warn about functions which might be candidates for format attributes. diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi index 726392409b6..4402b0427ef 100644 --- a/gcc/doc/invoke.texi +++ b/gcc/doc/invoke.texi @@ -398,7 +398,7 @@ Objective-C and Objective-C++ Dialects}. -Wstrict-aliasing=n -Wstrict-overflow -Wstrict-overflow=@var{n} @gol -Wstring-compare @gol -Wno-stringop-overflow -Wno-stringop-overread @gol --Wno-stringop-truncation @gol +-Wno-stringop-truncation -Wstrict-flex-arrays @gol -Wsuggest-attribute=@r{[}pure@r{|}const@r{|}noreturn@r{|}format@r{|}malloc@r{]} @gol -Wswitch -Wno-switch-bool -Wswitch-default -Wswitch-enum @gol -Wno-switch-outside-range -Wno-switch-unreachable -Wsync-nand @gol @@ -7835,6 +7835,31 @@ however, are not suitable arguments to functions that expect such arrays GCC issues warnings unless it can prove that the use is safe. @xref{Common Variable Attributes}. +@item -Wstrict-flex-arrays +@opindex Wstrict-flex-arrays +@opindex Wno-strict-flex-arrays +Warn about inproper usages of flexible array members +according to the @var{level} of the @code{strict_flex_array (@var{level})} +attribute attached to the trailing array field of a structure if it's +available, otherwise according to the @var{level} of the option +@option{-fstrict-flex-arrays=@var{level}}. + +This option is effective only when @var{level} is bigger than 0. Otherwise, +it will be ignored with a warning. + +when @var{level}=1, warnings will be issued for a trailing array reference +of a structure that have 2 or more elements if the trailing array is referenced +as a flexible array member. + +when @var{level}=2, in addition to @var{level}=1, additional warnings will be +issued for a trailing one-element array reference of a structure +if the array is referenced as a flexible array member. + +when @var{level}=3, in addition to @var{level}=2, additional warnings will be +issued for a trailing zero-length array reference of a structure +if the array is referenced as a flexible array member. + + @item -Wsuggest-attribute=@r{[}pure@r{|}const@r{|}noreturn@r{|}format@r{|}cold@r{|}malloc@r{]} @opindex Wsuggest-attribute= @opindex Wno-suggest-attribute= diff --git a/gcc/gimple-array-bounds.cc b/gcc/gimple-array-bounds.cc index db3459af325..825f11331b5 100644 --- a/gcc/gimple-array-bounds.cc +++ b/gcc/gimple-array-bounds.cc @@ -252,25 +252,34 @@ get_up_bounds_for_array_ref (tree ref, tree *decl, /* Given the LOW_SUB_ORG, LOW_SUB and UP_SUB, and the computed UP_BOUND and UP_BOUND_P1, check whether the array reference REF is out of bound. - Issue warnings if out of bound, return TRUE if warnings are issued. */ + When out of bounds, set OUT_OF_BOUND to true. + Issue warnings if FOR_ARRAY_BOUND is true. + return TRUE if warnings are issued. */ + static bool check_out_of_bounds_and_warn (location_t location, tree ref, tree low_sub_org, tree low_sub, tree up_sub, tree up_bound, tree up_bound_p1, const value_range *vr, - bool ignore_off_by_one) + bool ignore_off_by_one, bool for_array_bound, + bool *out_of_bound) { tree low_bound = array_ref_low_bound (ref); tree artype = TREE_TYPE (TREE_OPERAND (ref, 0)); bool warned = false; + *out_of_bound = false; /* Empty array. */ if (up_bound && tree_int_cst_equal (low_bound, up_bound_p1)) - warned = warning_at (location, OPT_Warray_bounds_, - "array subscript %E is outside array bounds of %qT", - low_sub_org, artype); + { + *out_of_bound = true; + if (for_array_bound) + warned = warning_at (location, OPT_Warray_bounds_, + "array subscript %E is outside array" + " bounds of %qT", low_sub_org, artype); + } if (warned) ; /* Do nothing. */ @@ -283,24 +292,33 @@ check_out_of_bounds_and_warn (location_t location, tree ref, : tree_int_cst_le (up_bound, up_sub)) && TREE_CODE (low_sub) == INTEGER_CST && tree_int_cst_le (low_sub, low_bound)) - warned = warning_at (location, OPT_Warray_bounds_, - "array subscript [%E, %E] is outside " - "array bounds of %qT", - low_sub, up_sub, artype); + { + *out_of_bound = true; + warned = warning_at (location, OPT_Warray_bounds_, + "array subscript [%E, %E] is outside " + "array bounds of %qT", + low_sub, up_sub, artype); + } } else if (up_bound && TREE_CODE (up_sub) == INTEGER_CST && (ignore_off_by_one ? !tree_int_cst_le (up_sub, up_bound_p1) : !tree_int_cst_le (up_sub, up_bound))) - warned = warning_at (location, OPT_Warray_bounds_, - "array subscript %E is above array bounds of %qT", - up_sub, artype); + { + *out_of_bound = true; + warned = warning_at (location, OPT_Warray_bounds_, + "array subscript %E is above array bounds of %qT", + up_sub, artype); + } else if (TREE_CODE (low_sub) == INTEGER_CST && tree_int_cst_lt (low_sub, low_bound)) - warned = warning_at (location, OPT_Warray_bounds_, - "array subscript %E is below array bounds of %qT", - low_sub, artype); + { + *out_of_bound = true; + warned = warning_at (location, OPT_Warray_bounds_, + "array subscript %E is below array bounds of %qT", + low_sub, artype); + } return warned; } @@ -333,14 +351,21 @@ array_bounds_checker::check_array_ref (location_t location, tree ref, tree arg = TREE_OPERAND (ref, 0); const bool compref = TREE_CODE (arg) == COMPONENT_REF; + unsigned int strict_flex_array_level = flag_strict_flex_arrays; if (compref) - /* Try to determine special array member type for this COMPONENT_REF. */ - sam = component_ref_sam_type (arg); + { + /* Try to determine special array member type for this COMPONENT_REF. */ + sam = component_ref_sam_type (arg); + /* Get the level of strict_flex_array for this array field. */ + tree afield_decl = TREE_OPERAND (arg, 1); + strict_flex_array_level = strict_flex_array_level_of (afield_decl); + } get_up_bounds_for_array_ref (ref, &decl, &up_bound, &up_bound_p1); bool warned = false; + bool out_of_bound = false; tree artype = TREE_TYPE (TREE_OPERAND (ref, 0)); tree low_sub_org = TREE_OPERAND (ref, 1); @@ -361,7 +386,8 @@ array_bounds_checker::check_array_ref (location_t location, tree ref, warned = check_out_of_bounds_and_warn (location, ref, low_sub_org, low_sub, up_sub, up_bound, up_bound_p1, vr, - ignore_off_by_one); + ignore_off_by_one, warn_array_bounds, + &out_of_bound); if (!warned && sam == special_array_member::int_0) @@ -373,19 +399,56 @@ array_bounds_checker::check_array_ref (location_t location, tree ref, "of an interior zero-length array %qT")), low_sub, artype); - if (warned) + if (warned || out_of_bound) { - if (dump_file && (dump_flags & TDF_DETAILS)) + if (warned && dump_file && (dump_flags & TDF_DETAILS)) { fprintf (dump_file, "Array bound warning for "); dump_generic_expr (MSG_NOTE, TDF_SLIM, ref); fprintf (dump_file, "\n"); } + /* issue warnings for -Wstrict-flex-arrays according to the level of + flag_strict_flex_arrays. */ + if (out_of_bound && warn_strict_flex_arrays) + switch (strict_flex_array_level) + { + case 3: + /* Issue additional warnings for trailing arrays [0]. */ + if (sam == special_array_member::trail_0) + warned = warning_at (location, OPT_Wstrict_flex_arrays, + "trailing array %qT should not be used as " + "a flexible array member for level 3", + artype); + /* FALLTHROUGH. */ + case 2: + /* Issue additional warnings for trailing arrays [1]. */ + if (sam == special_array_member::trail_1) + warned = warning_at (location, OPT_Wstrict_flex_arrays, + "trailing array %qT should not be used as " + "a flexible array member for level 2 and " + "above", artype); + /* FALLTHROUGH. */ + case 1: + /* Issue warnings for trailing arrays [n]. */ + if (sam == special_array_member::trail_n) + warned = warning_at (location, OPT_Wstrict_flex_arrays, + "trailing array %qT should not be used as " + "a flexible array member for level 1 and " + "above", artype); + break; + case 0: + /* Do nothing. */ + break; + default: + gcc_unreachable (); + } + /* Avoid more warnings when checking more significant subscripts of the same expression. */ ref = TREE_OPERAND (ref, 0); suppress_warning (ref, OPT_Warray_bounds_); + suppress_warning (ref, OPT_Wstrict_flex_arrays); if (decl) ref = decl; diff --git a/gcc/opts.cc b/gcc/opts.cc index 73fc97756e4..8db53ad6c77 100644 --- a/gcc/opts.cc +++ b/gcc/opts.cc @@ -1411,6 +1411,14 @@ finish_options (struct gcc_options *opts, struct gcc_options *opts_set, opts->x_profile_flag = 0; } + if (opts->x_warn_strict_flex_arrays) + if (opts->x_flag_strict_flex_arrays == 0) + { + opts->x_warn_strict_flex_arrays = 0; + warning_at (UNKNOWN_LOCATION, 0, + "%<-Wstrict-flex-arrays%> is ignored when" + " %<-fstrict-flex-arrays%> does not present"); + } diagnose_options (opts, opts_set, loc); } diff --git a/gcc/testsuite/c-c++-common/Wstrict-flex-arrays.c b/gcc/testsuite/c-c++-common/Wstrict-flex-arrays.c new file mode 100644 index 00000000000..72b4b7c6406 --- /dev/null +++ b/gcc/testsuite/c-c++-common/Wstrict-flex-arrays.c @@ -0,0 +1,9 @@ +/* Test the usage of option -Wstrict-flex-arrays. */ +/* { dg-do compile } */ +/* { dg-options "-O2 -Wstrict-flex-arrays" } */ + +int main(int argc, char *argv[]) +{ + return 0; +} +/* { dg-warning "is ignored when \'-fstrict-flex-arrays\' does not present" "" { target *-*-* } 0 } */ diff --git a/gcc/testsuite/gcc.dg/Warray-bounds-flex-arrays-1.c b/gcc/testsuite/gcc.dg/Warray-bounds-flex-arrays-1.c index d36ba4d86cb..65c9fec43af 100644 --- a/gcc/testsuite/gcc.dg/Warray-bounds-flex-arrays-1.c +++ b/gcc/testsuite/gcc.dg/Warray-bounds-flex-arrays-1.c @@ -1,6 +1,6 @@ -/* Test -fstrict-flex-arrays + -Warray-bounds. */ +/* Test -fstrict-flex-arrays + -Warray-bounds + -Wstrict-flex-arrays. */ /* { dg-do compile} */ -/* { dg-options "-O2 -fstrict-flex-arrays=1 -Warray-bounds" } */ +/* { dg-options "-O2 -Wstrict-flex-arrays -fstrict-flex-arrays=1 -Warray-bounds" } */ struct trailing_array_1 { int a; @@ -32,6 +32,7 @@ void __attribute__((__noinline__)) stuff( struct trailing_array_4 *trailing_flex) { normal->c[5] = 5; /*{ dg-warning "array subscript 5 is above array bounds of" } */ + /*{ dg-warning "should not be used as a flexible array member for level 1 and above" "" { target *-*-* } .-1 } */ trailing_1->c[2] = 2; /* { dg-bogus "array subscript " } */ trailing_0->c[1] = 1; /* { dg-bogus "array subscript " } */ trailing_flex->c[10] = 10; /* { dg-bogus "array subscript " } */ diff --git a/gcc/testsuite/gcc.dg/Warray-bounds-flex-arrays-2.c b/gcc/testsuite/gcc.dg/Warray-bounds-flex-arrays-2.c index f63206e1948..2b5a895c598 100644 --- a/gcc/testsuite/gcc.dg/Warray-bounds-flex-arrays-2.c +++ b/gcc/testsuite/gcc.dg/Warray-bounds-flex-arrays-2.c @@ -1,6 +1,6 @@ -/* Test -fstrict-flex-arrays + -Warray-bounds. */ +/* Test -fstrict-flex-arrays + -Warray-bounds + -Wstrict-flex-arrays. */ /* { dg-do compile } */ -/* { dg-options "-O2 -fstrict-flex-arrays=2 -Warray-bounds" } */ +/* { dg-options "-O2 -Wstrict-flex-arrays -fstrict-flex-arrays=2 -Warray-bounds" } */ struct trailing_array_1 { int a; @@ -32,7 +32,9 @@ void __attribute__((__noinline__)) stuff( struct trailing_array_4 *trailing_flex) { normal->c[5] = 5; /*{ dg-warning "array subscript 5 is above array bounds of" } */ + /*{ dg-warning "should not be used as a flexible array member for level 1 and above" "" { target *-*-* } .-1 } */ trailing_1->c[2] = 2; /* { dg-warning "array subscript 2 is above array bounds of" } */ + /* { dg-warning "should not be used as a flexible array member for level 2 and above" "" { target *-*-* } .-1 } */ trailing_0->c[1] = 1; /* { dg-bogus "array subscript " } */ trailing_flex->c[10] = 10; /* { dg-bogus "array subscript " } */ diff --git a/gcc/testsuite/gcc.dg/Warray-bounds-flex-arrays-3.c b/gcc/testsuite/gcc.dg/Warray-bounds-flex-arrays-3.c index e3273714e8b..25b903f2615 100644 --- a/gcc/testsuite/gcc.dg/Warray-bounds-flex-arrays-3.c +++ b/gcc/testsuite/gcc.dg/Warray-bounds-flex-arrays-3.c @@ -1,6 +1,6 @@ -/* Test -fstrict-flex-arrays + -Warray-bounds. */ +/* Test -fstrict-flex-arrays + -Warray-bounds + -Wstrict-flex-arrays. */ /* { dg-do compile } */ -/* { dg-options "-O2 -fstrict-flex-arrays=3 -Warray-bounds" } */ +/* { dg-options "-O2 -Wstrict-flex-arrays -fstrict-flex-arrays=3 -Warray-bounds" } */ struct trailing_array_1 { int a; @@ -32,8 +32,11 @@ void __attribute__((__noinline__)) stuff( struct trailing_array_4 *trailing_flex) { normal->c[5] = 5; /*{ dg-warning "array subscript 5 is above array bounds of" } */ + /*{ dg-warning "should not be used as a flexible array member for level 1 and above" "" { target *-*-* } .-1 } */ trailing_1->c[2] = 2; /*{ dg-warning "array subscript 2 is above array bounds of" } */ + /* { dg-warning "should not be used as a flexible array member for level 2 and above" "" { target *-*-* } .-1 } */ trailing_0->c[1] = 1; /*{ dg-warning "array subscript 1 is outside array bounds of" } */ + /* { dg-warning "should not be used as a flexible array member for level 3" "" { target *-*-* } .-1 } */ trailing_flex->c[10] = 10; /* { dg-bogus "array subscript" } */ } diff --git a/gcc/testsuite/gcc.dg/Warray-bounds-flex-arrays-4.c b/gcc/testsuite/gcc.dg/Warray-bounds-flex-arrays-4.c index cabaea77dc2..5fc500a19ca 100644 --- a/gcc/testsuite/gcc.dg/Warray-bounds-flex-arrays-4.c +++ b/gcc/testsuite/gcc.dg/Warray-bounds-flex-arrays-4.c @@ -1,6 +1,6 @@ -/* Test -fstrict-flex-arrays + -Warray-bounds=2. */ +/* Test -fstrict-flex-arrays + -Warray-bounds=2 + -Wstrict-flex-arrays. */ /* { dg-do compile } */ -/* { dg-options "-O2 -fstrict-flex-arrays=1 -Warray-bounds=2" } */ +/* { dg-options "-O2 -Wstrict-flex-arrays -fstrict-flex-arrays=1 -Warray-bounds=2" } */ struct trailing_array_1 { int a; @@ -32,6 +32,7 @@ void __attribute__((__noinline__)) stuff( struct trailing_array_4 *trailing_flex) { normal->c[5] = 5; /*{ dg-warning "array subscript 5 is above array bounds of" } */ + /*{ dg-warning "should not be used as a flexible array member for level 1 and above" "" { target *-*-* } .-1 } */ trailing_1->c[2] = 2; /* { dg-bogus "array subscript " } */ trailing_0->c[1] = 1; /* { dg-bogus "array subscript " } */ trailing_flex->c[10] = 10; /* { dg-bogus "array subscript " } */ diff --git a/gcc/testsuite/gcc.dg/Warray-bounds-flex-arrays-5.c b/gcc/testsuite/gcc.dg/Warray-bounds-flex-arrays-5.c index 8b7db6e4f39..30bb4ca8832 100644 --- a/gcc/testsuite/gcc.dg/Warray-bounds-flex-arrays-5.c +++ b/gcc/testsuite/gcc.dg/Warray-bounds-flex-arrays-5.c @@ -1,6 +1,6 @@ -/* Test -fstrict-flex-arrays + -Warray-bounds=2. */ +/* Test -fstrict-flex-arrays + -Warray-bounds=2 + -Wstrict-flex-arrays. */ /* { dg-do compile } */ -/* { dg-options "-O2 -fstrict-flex-arrays=2 -Warray-bounds=2" } */ +/* { dg-options "-O2 -Wstrict-flex-arrays -fstrict-flex-arrays=2 -Warray-bounds=2" } */ struct trailing_array_1 { int a; @@ -32,7 +32,9 @@ void __attribute__((__noinline__)) stuff( struct trailing_array_4 *trailing_flex) { normal->c[5] = 5; /*{ dg-warning "array subscript 5 is above array bounds of" } */ + /*{ dg-warning "should not be used as a flexible array member for level 1 and above" "" { target *-*-* } .-1 } */ trailing_1->c[2] = 2; /*{ dg-warning "array subscript 2 is above array bounds of" } */ + /* { dg-warning "should not be used as a flexible array member for level 2 and above" "" { target *-*-* } .-1 } */ trailing_0->c[1] = 1; /* { dg-bogus "array subscript " } */ trailing_flex->c[10] = 10; /* { dg-bogus "array subscript " } */ diff --git a/gcc/testsuite/gcc.dg/Warray-bounds-flex-arrays-6.c b/gcc/testsuite/gcc.dg/Warray-bounds-flex-arrays-6.c index 035bf481396..e847a44516e 100644 --- a/gcc/testsuite/gcc.dg/Warray-bounds-flex-arrays-6.c +++ b/gcc/testsuite/gcc.dg/Warray-bounds-flex-arrays-6.c @@ -1,6 +1,6 @@ -/* Test -fstrict-flex-arrays + -Warray-bounds=2. */ +/* Test -fstrict-flex-arrays + -Warray-bounds=2 + -Wstrict-flex-arrays. */ /* { dg-do compile } */ -/* { dg-options "-O2 -fstrict-flex-arrays=3 -Warray-bounds=2" } */ +/* { dg-options "-O2 -Wstrict-flex-arrays -fstrict-flex-arrays=3 -Warray-bounds=2" } */ struct trailing_array_1 { int a; @@ -32,8 +32,11 @@ void __attribute__((__noinline__)) stuff( struct trailing_array_4 *trailing_flex) { normal->c[5] = 5; /*{ dg-warning "array subscript 5 is above array bounds of" } */ + /*{ dg-warning "should not be used as a flexible array member for level 1 and above" "" { target *-*-* } .-1 } */ trailing_1->c[2] = 2; /*{ dg-warning "array subscript 2 is above array bounds of" } */ + /* { dg-warning "should not be used as a flexible array member for level 2 and above" "" { target *-*-* } .-1 } */ trailing_0->c[1] = 1; /*{ dg-warning "array subscript 1 is outside array bounds of" } */ + /* { dg-warning "should not be used as a flexible array member for level 3" "" { target *-*-* } .-1 } */ trailing_flex->c[10] = 10; /* { dg-bogus "array subscript " } */ } diff --git a/gcc/testsuite/gcc.dg/Wstrict-flex-arrays-2.c b/gcc/testsuite/gcc.dg/Wstrict-flex-arrays-2.c new file mode 100644 index 00000000000..2e241f96208 --- /dev/null +++ b/gcc/testsuite/gcc.dg/Wstrict-flex-arrays-2.c @@ -0,0 +1,39 @@ +/* Test -Wstrict-flex-arrays. */ +/* { dg-do compile } */ +/* { dg-options "-O2 -Wstrict-flex-arrays -fstrict-flex-arrays=2" } */ + +struct trailing_array_1 { + int a; + int b; + int c[4]; +}; + +struct trailing_array_2 { + int a; + int b; + int c[1]; +}; + +struct trailing_array_3 { + int a; + int b; + int c[0]; +}; +struct trailing_array_4 { + int a; + int b; + int c[]; +}; + +void __attribute__((__noinline__)) stuff( + struct trailing_array_1 *normal, + struct trailing_array_2 *trailing_1, + struct trailing_array_3 *trailing_0, + struct trailing_array_4 *trailing_flex) +{ + normal->c[5] = 5; /*{ dg-warning "should not be used as a flexible array member for level 1 and above" } */ + trailing_1->c[2] = 2; /* { dg-warning "should not be used as a flexible array member for level 2 and above" } */ + trailing_0->c[1] = 1; /* { dg-bogus "should not be used as a flexible array member for level 2 and above" } */ + trailing_flex->c[10] = 10; /* { dg-bogus "should not be used as a flexible array member for level 2 and above" } */ + +} diff --git a/gcc/testsuite/gcc.dg/Wstrict-flex-arrays-3.c b/gcc/testsuite/gcc.dg/Wstrict-flex-arrays-3.c new file mode 100644 index 00000000000..97eb65ba0a9 --- /dev/null +++ b/gcc/testsuite/gcc.dg/Wstrict-flex-arrays-3.c @@ -0,0 +1,39 @@ +/* Test -Wstrict-flex-arrays. */ +/* { dg-do compile } */ +/* { dg-options "-O2 -Wstrict-flex-arrays -fstrict-flex-arrays=3" } */ + +struct trailing_array_1 { + int a; + int b; + int c[4]; +}; + +struct trailing_array_2 { + int a; + int b; + int c[1]; +}; + +struct trailing_array_3 { + int a; + int b; + int c[0]; +}; +struct trailing_array_4 { + int a; + int b; + int c[]; +}; + +void __attribute__((__noinline__)) stuff( + struct trailing_array_1 *normal, + struct trailing_array_2 *trailing_1, + struct trailing_array_3 *trailing_0, + struct trailing_array_4 *trailing_flex) +{ + normal->c[5] = 5; /*{ dg-warning "should not be used as a flexible array member for level 1 and above" } */ + trailing_1->c[2] = 2; /* { dg-warning "should not be used as a flexible array member for level 2 and above" } */ + trailing_0->c[1] = 1; /* { dg-warning "should not be used as a flexible array member for level 3" } */ + trailing_flex->c[10] = 10; /* { dg-bogus "should not be used as a flexible array member for level 3" } */ + +} diff --git a/gcc/testsuite/gcc.dg/Wstrict-flex-arrays.c b/gcc/testsuite/gcc.dg/Wstrict-flex-arrays.c new file mode 100644 index 00000000000..110fdc72778 --- /dev/null +++ b/gcc/testsuite/gcc.dg/Wstrict-flex-arrays.c @@ -0,0 +1,39 @@ +/* Test -Wstrict-flex-arrays. */ +/* { dg-do compile } */ +/* { dg-options "-O2 -Wstrict-flex-arrays -fstrict-flex-arrays=1" } */ + +struct trailing_array_1 { + int a; + int b; + int c[4]; +}; + +struct trailing_array_2 { + int a; + int b; + int c[1]; +}; + +struct trailing_array_3 { + int a; + int b; + int c[0]; +}; +struct trailing_array_4 { + int a; + int b; + int c[]; +}; + +void __attribute__((__noinline__)) stuff( + struct trailing_array_1 *normal, + struct trailing_array_2 *trailing_1, + struct trailing_array_3 *trailing_0, + struct trailing_array_4 *trailing_flex) +{ + normal->c[5] = 5; /*{ dg-warning "should not be used as a flexible array member for level 1 and above" } */ + trailing_1->c[2] = 2; /* { dg-bogus "should not be used as a flexible array member for level 1 and above" } */ + trailing_0->c[1] = 1; /* { dg-bogus "should not be used as a flexible array member for level 1 and above" } */ + trailing_flex->c[10] = 10; /* { dg-bogus "should not be used as a flexible array member for level 1 and above" } */ + +} diff --git a/gcc/tree-vrp.cc b/gcc/tree-vrp.cc index 3846dc1d849..e6c6c5a301d 100644 --- a/gcc/tree-vrp.cc +++ b/gcc/tree-vrp.cc @@ -1087,7 +1087,7 @@ execute_ranger_vrp (struct function *fun, bool warn_array_bounds_p, if (dump_file && (dump_flags & TDF_DETAILS)) ranger->dump (dump_file); - if (warn_array_bounds && warn_array_bounds_p) + if ((warn_array_bounds || warn_strict_flex_arrays) && warn_array_bounds_p) { // Set all edges as executable, except those ranger says aren't. int non_exec_flag = ranger->non_executable_edge_flag;