From: Martin Sebor Date: Thu, 7 Jan 2021 21:20:39 +0000 (-0700) Subject: PR middle-end/98578 - ICE warning on uninitialized VLA access X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=178f0afce3611282170de380fcea9db9d6e3ff0c;p=gcc.git PR middle-end/98578 - ICE warning on uninitialized VLA access gcc/c-family/ChangeLog: PR middle-end/98578 * c-pretty-print.c (print_mem_ref): Strip array from access type. Avoid assuming acces type's size is constant. Correct condition guarding the printing of a parenthesis. gcc/testsuite/ChangeLog: PR middle-end/98578 * gcc.dg/plugin/gil-1.c: Adjust expected output. * gcc.dg/uninit-pr98578.c: New test. --- diff --git a/gcc/c-family/c-pretty-print.c b/gcc/c-family/c-pretty-print.c index e963cf53091..87301a2091c 100644 --- a/gcc/c-family/c-pretty-print.c +++ b/gcc/c-family/c-pretty-print.c @@ -1844,22 +1844,25 @@ print_mem_ref (c_pretty_printer *pp, tree e) } } - const tree access_type = TREE_TYPE (e); + tree access_type = TREE_TYPE (e); + if (TREE_CODE (access_type) == ARRAY_TYPE) + access_type = TREE_TYPE (access_type); tree arg_type = TREE_TYPE (TREE_TYPE (arg)); if (TREE_CODE (arg_type) == ARRAY_TYPE) arg_type = TREE_TYPE (arg_type); if (tree access_size = TYPE_SIZE_UNIT (access_type)) - { - /* For naturally aligned accesses print the nonzero offset - in units of the accessed type, in the form of an index. - For unaligned accesses also print the residual byte offset. */ - offset_int asize = wi::to_offset (access_size); - offset_int szlg2 = wi::floor_log2 (asize); - - elt_idx = byte_off >> szlg2; - byte_off = byte_off - (elt_idx << szlg2); - } + if (TREE_CODE (access_size) == INTEGER_CST) + { + /* For naturally aligned accesses print the nonzero offset + in units of the accessed type, in the form of an index. + For unaligned accesses also print the residual byte offset. */ + offset_int asize = wi::to_offset (access_size); + offset_int szlg2 = wi::floor_log2 (asize); + + elt_idx = byte_off >> szlg2; + byte_off = byte_off - (elt_idx << szlg2); + } /* True to include a cast to the accessed type. */ const bool access_cast = VOID_TYPE_P (arg_type) @@ -1924,9 +1927,9 @@ print_mem_ref (c_pretty_printer *pp, tree e) } if (elt_idx != 0) { - if (byte_off == 0 && char_cast) + if (access_cast || char_cast) pp_c_right_paren (pp); - pp_c_right_paren (pp); + if (addr) { pp_space (pp); diff --git a/gcc/testsuite/gcc.dg/plugin/gil-1.c b/gcc/testsuite/gcc.dg/plugin/gil-1.c index 4e8f535ba85..66872f07466 100644 --- a/gcc/testsuite/gcc.dg/plugin/gil-1.c +++ b/gcc/testsuite/gcc.dg/plugin/gil-1.c @@ -13,7 +13,7 @@ void test_2 (PyObject *obj) { Py_BEGIN_ALLOW_THREADS /* { dg-message "releasing the GIL here" } */ - Py_INCREF (obj); /* { dg-warning "use of PyObject '\\*\\(obj\\)' without the GIL" } */ + Py_INCREF (obj); /* { dg-warning "use of PyObject '\\*obj' without the GIL" } */ Py_DECREF (obj); Py_END_ALLOW_THREADS @@ -60,7 +60,7 @@ void test_5 (PyObject *obj) static void __attribute__((noinline)) called_by_test_6 (PyObject *obj) { - Py_INCREF (obj); /* { dg-warning "use of PyObject '\\*\\(obj\\)' without the GIL" } */ + Py_INCREF (obj); /* { dg-warning "use of PyObject '\\*obj' without the GIL" } */ Py_DECREF (obj); } diff --git a/gcc/testsuite/gcc.dg/uninit-pr98578.c b/gcc/testsuite/gcc.dg/uninit-pr98578.c new file mode 100644 index 00000000000..98d611757ab --- /dev/null +++ b/gcc/testsuite/gcc.dg/uninit-pr98578.c @@ -0,0 +1,110 @@ +/* PR middle-end/98578 - ICE warning on uninitialized VLA access + { dg-do compile } + { dg-options "-O2 -Wall" } */ + +void* malloc (__SIZE_TYPE__); + +void T (int, ...); + +void vla_n (int n, int i) +{ + int a1[n]; + + /* a1[I] should be formatted as as a1[I] (or, for I == 0, perhaps + as *a1), but definitely not as *a1[I]. This is a bug in VLA + formatting. */ + T (a1[0]); // { dg-warning "'a1\\\[0]' is used uninitialized" "pr98587" { xfail *-*-* } } + // { dg-warning "'\\*a1\\\[0]' is used uninitialized" "spurious star" { target *-*-* } .-1 } + T (a1[1]); // { dg-warning "a1\\\[1]' is used uninitialized" } + T (a1[i]); // { dg-warning "a1\\\[i]' is used uninitialized" } +} + +void vla_n_2 (int n, int i) +{ + int a2[n][2]; + + T (a2[0][0]); // { dg-warning "a2\\\[0]\\\[0]' is used uninitialized" } + T (a2[2][1]); // { dg-warning "a2\\\[2]\\\[1]' is used uninitialized" } + T (a2[3][i]); // { dg-warning "a2\\\[3]\\\[i]' is used uninitialized" } + T (a2[i][0]); // { dg-warning "a2\\\[i]\\\[0]' is used uninitialized" } + T (a2[i][i]); // { dg-warning "a2\\\[i]\\\[i]' is used uninitialized" } +} + + +void vla_3_n (int n, int i) +{ + int a2[3][n]; + + T (a2[0][0]); // { dg-warning "a2\\\[0]\\\[0]' is used uninitialized" } + T (a2[1][2]); // { dg-warning "a2\\\[1]\\\[2]' is used uninitialized" } + T (a2[2][i]); // { dg-warning "a2\\\[2]\\\[i]' is used uninitialized" } + T (a2[i][3]); // { dg-warning "a2\\\[i]\\\[3]' is used uninitialized" } + T (a2[i][i]); // { dg-warning "a2\\\[i]\\\[i]' is used uninitialized" } +} + + +void vla_n_n (int n, int i) +{ + int a2[n][n]; + + T (a2[0][0]); // { dg-warning "a2\\\[0]\\\[0]' is used uninitialized" } + T (a2[4][5]); // { dg-warning "a2\\\[4]\\\[5]' is used uninitialized" } + T (a2[6][i]); // { dg-warning "a2\\\[6]\\\[i]' is used uninitialized" } + T (a2[i][7]); // { dg-warning "a2\\\[i]\\\[7]' is used uninitialized" } + T (a2[i][i]); // { dg-warning "a2\\\[i]\\\[i]' is used uninitialized" } +} + + +void char_ptr_n (int n, int i) +{ + char *p = malloc (n); + + T (p[0]); // { dg-warning "'\\\*p' is used uninitialized" } + T (p[1]); // { dg-warning "'p\\\[1]' is used uninitialized" } + T (p[i]); // { dg-warning "'p\\\[i]' is used uninitialized" "pr98587" { xfail *-*-* } } + // { dg-warning "is used uninitialized" "POINTER_PLUS_EXPR" { target *-*-* } .-1 } +} + + +void int_ptr_n (int n, int i) +{ + int *p = malloc (n); + + T (p[0]); // { dg-warning "'\\\*p' is used uninitialized" } + T (p[1]); // { dg-warning "'p\\\[1]' is used uninitialized" } + T (p[i]); // { dg-warning "'p\\\[i]' is used uninitialized" "pr98587" { xfail *-*-* } } + // { dg-warning "is used uninitialized" "POINTER_PLUS_EXPR" { target *-*-* } .-1 } +} + + +void int_arr_ptr_n (int n, int i) +{ + int (*p)[n] = malloc (n); + + T ((*p)[0]); // { dg-warning "\\(\\*p\\)\\\[0]' is used uninitialized" "pr98587" { xfail *-*-* } } + // { dg-warning "\\*p\\\[0]' is used uninitialized" "missing parens" { target *-*-* } .-1 } + T ((*p)[1]); // { dg-warning "\\(\\*p\\)\\\[1]' is used uninitialized" "pr98587" { xfail *-*-* } } + // { dg-warning "\\*p\\\[1]' is used uninitialized" "missing parens" { target *-*-* } .-1 } + T ((*p)[i]); // { dg-warning "\\(\\*p\\)\\\[i]' is used uninitialized" "pr98587" { xfail *-*-* } } + // { dg-warning "\\*p\\\[i]' is used uninitialized" "missing parens" { target *-*-* } .-1 } +} + + +void int_arr_ptr_n_n (int n, int i) +{ + int (*p)[n][n] = malloc (n); + + T ((*p)[0][0]); // { dg-warning "\\(\\*p\\)\\\[0]\\\[0]' is used uninitialized" "pr98587" { xfail *-*-* } } + // { dg-warning "\\*p\\\[0]\\\[0]' is used uninitialized" "missing parens" { target *-*-* } .-1 } + T ((*p)[1][2]); // { dg-warning "\\(\\*p\\)\\\[1]\\\[2]' is used uninitialized" "pr98587" { xfail *-*-* } } + // { dg-warning "\\*p\\\[1]\\\[2]' is used uninitialized" "missing parens" { target *-*-* } .-1 } + T ((*p)[0][i]); // { dg-warning "\\(\\*p\\)\\\[0]\\\[i]' is used uninitialized" "pr98587" { xfail *-*-* } } + // { dg-warning "\\*p\\\[0]\\\[i]' is used uninitialized" "missing parens" { target *-*-* } .-1 } + T ((*p)[3][i]); // { dg-warning "\\(\\*p\\)\\\[3]\\\[i]' is used uninitialized" "pr98587" { xfail *-*-* } } + // { dg-warning "\\*p\\\[3]\\\[i]' is used uninitialized" "missing parens" { target *-*-* } .-1 } + T ((*p)[i][i]); // { dg-warning "\\(\\*p\\)\\\[i]\\\[i]' is used uninitialized" "pr98587" { xfail *-*-* } } + // { dg-warning "\\*p\\\[i]\\\[i]' is used uninitialized" "missing parens" { target *-*-* } .-1 } + + T ((*p)[i][i + 1]); // { dg-warning "\\(\\*p\\)\\\[i]\\\[i \\+ 1]' is used uninitialized" "pr98588" { xfail *-*-* } } + // { dg-warning "\\*p\\\[i]\\\[]' is used uninitialized" "missing parens" { target *-*-* } .-1 } +}