The array descriptor language hook can hold the description of a limited number of array dimensions. This macro will ease preventing overflow in front-ends.
gcc/ada/ChangeLog: * gcc-interface/misc.c (gnat_get_array_descr_info): When the array has more dimensions than the language hook can handle, fall back to a nested arrays description. Handle context-less array types. gcc/ChangeLog: * dwarf2out.h (DWARF2OUT_ARRAY_DESCR_INFO_MAX_DIMEN): New macro. (struct array_descr_info): Use it for the dimensions array's size. * dwarf2out.c (gen_type_die_with_usage): Check that the array descr. language hook does not return an array with more dimensions that it should. -- Pierre-Marie de Rodat
>From 5221a4fadfa84f31cc97e0eba26f8640c9abe70d Mon Sep 17 00:00:00 2001 From: Pierre-Marie de Rodat <dero...@adacore.com> Date: Fri, 21 Nov 2014 22:20:02 +0100 Subject: [PATCH 6/8] DWARF: create a macro for max dimensions for array descr. lang. hook The array descriptor language hook can hold the description of a limited number of array dimensions. This macro will ease preventing overflow in front-ends. gcc/ada/ChangeLog: * gcc-interface/misc.c (gnat_get_array_descr_info): When the array has more dimensions than the language hook can handle, fall back to a nested arrays description. Handle context-less array types. gcc/ChangeLog: * dwarf2out.h (DWARF2OUT_ARRAY_DESCR_INFO_MAX_DIMEN): New macro. (struct array_descr_info): Use it for the dimensions array's size. * dwarf2out.c (gen_type_die_with_usage): Check that the array descr. language hook does not return an array with more dimensions that it should. --- gcc/ada/gcc-interface/misc.c | 16 +++++++++++++++- gcc/dwarf2out.c | 4 ++++ gcc/dwarf2out.h | 4 +++- 3 files changed, 22 insertions(+), 2 deletions(-) diff --git a/gcc/ada/gcc-interface/misc.c b/gcc/ada/gcc-interface/misc.c index 318f566..4a355a3 100644 --- a/gcc/ada/gcc-interface/misc.c +++ b/gcc/ada/gcc-interface/misc.c @@ -848,7 +848,20 @@ gnat_get_array_descr_info (const_tree type, struct array_descr_info *info) break; last_dimen = dimen; } + info->ndimensions = i; + + /* Too many dimensions? Give up generating proper description: yield instead + nested arrays. Note that in this case, this hook is invoked once on each + intermediate array type: be consistent and output nested arrays for all + dimensions. */ + if (info->ndimensions > DWARF2OUT_ARRAY_DESCR_INFO_MAX_DIMEN + || TYPE_MULTI_ARRAY_P (first_dimen)) + { + info->ndimensions = 1; + last_dimen = first_dimen; + } + info->element_type = TREE_TYPE (last_dimen); /* Now iterate over all dimensions in source-order and fill the info @@ -873,7 +886,8 @@ gnat_get_array_descr_info (const_tree type, struct array_descr_info *info) expressions: arrays that are constrained by record discriminants and XUA types. */ const bool is_xua_type = - (TREE_CODE (TYPE_CONTEXT (first_dimen)) != RECORD_TYPE + (TYPE_CONTEXT (first_dimen) != NULL_TREE + && TREE_CODE (TYPE_CONTEXT (first_dimen)) != RECORD_TYPE && contains_placeholder_p (TYPE_MIN_VALUE (index_type))); if (is_xua_type && gnat_encodings != DWARF_GNAT_ENCODINGS_MINIMAL) diff --git a/gcc/dwarf2out.c b/gcc/dwarf2out.c index 2653c67..d989264 100644 --- a/gcc/dwarf2out.c +++ b/gcc/dwarf2out.c @@ -22454,6 +22454,10 @@ gen_type_die_with_usage (tree type, dw_die_ref context_die, memset (&info, 0, sizeof (info)); if (lang_hooks.types.get_array_descr_info (type, &info)) { + /* Fortran sometimes emits array types with no dimension. */ + gcc_assert (info.ndimensions >= 0 + && (info.ndimensions + <= DWARF2OUT_ARRAY_DESCR_INFO_MAX_DIMEN)); gen_descr_array_type_die (type, &info, context_die); TREE_ASM_WRITTEN (type) = 1; return; diff --git a/gcc/dwarf2out.h b/gcc/dwarf2out.h index 655d91a..a2049d0 100644 --- a/gcc/dwarf2out.h +++ b/gcc/dwarf2out.h @@ -318,6 +318,8 @@ enum array_descr_ordering array_descr_ordering_column_major }; +#define DWARF2OUT_ARRAY_DESCR_INFO_MAX_DIMEN 16 + struct array_descr_info { int ndimensions; @@ -341,7 +343,7 @@ struct array_descr_info /* Only Fortran uses more than one dimension for array types. For other languages, the stride can be rather specified for the whole array. */ tree stride; - } dimen[10]; + } dimen[DWARF2OUT_ARRAY_DESCR_INFO_MAX_DIMEN]; }; enum fixed_point_scale_factor -- 2.4.5