#include "tree-diagnostic.h"
#include "langhooks.h"
#include "langhooks-def.h"
+#include "vec.h"
/* Prints out, if necessary, the name of the current function
that caused an error. Called from all error and warning functions. */
diagnostic_report_current_function (diagnostic_context *context,
diagnostic_info *diagnostic)
{
- diagnostic_report_current_module (context);
+ diagnostic_report_current_module (context, diagnostic->location);
lang_hooks.print_error_function (context, input_filename, diagnostic);
}
diagnostic_info *diagnostic)
{
diagnostic_report_current_function (context, diagnostic);
- pp_set_prefix (context->printer, diagnostic_build_prefix (diagnostic));
+ pp_set_prefix (context->printer, diagnostic_build_prefix (context,
+ diagnostic));
+}
+
+/* This is a pair made of a location and the line map it originated
+ from. It's used in the maybe_unwind_expanded_macro_loc function
+ below. */
+typedef struct
+{
+ const struct line_map *map;
+ source_location where;
+} loc_map_pair;
+
+DEF_VEC_O (loc_map_pair);
+DEF_VEC_ALLOC_O (loc_map_pair, heap);
+
+/* Unwind the different macro expansions that lead to the token which
+ location is WHERE and emit diagnostics showing the resulting
+ unwound macro expansion trace. Let's look at an example to see how
+ the trace looks like. Suppose we have this piece of code,
+ artificially annotated with the line numbers to increase
+ legibility:
+
+ $ cat -n test.c
+ 1 #define OPERATE(OPRD1, OPRT, OPRD2) \
+ 2 OPRD1 OPRT OPRD2;
+ 3
+ 4 #define SHIFTL(A,B) \
+ 5 OPERATE (A,<<,B)
+ 6
+ 7 #define MULT(A) \
+ 8 SHIFTL (A,1)
+ 9
+ 10 void
+ 11 g ()
+ 12 {
+ 13 MULT (1.0);// 1.0 << 1; <-- so this is an error.
+ 14 }
+
+ Here is the diagnostic that we want the compiler to generate:
+
+ test.c: In function 'g':
+ test.c:5:14: error: invalid operands to binary << (have 'double' and 'int')
+ test.c:2:9: note: in expansion of macro 'OPERATE'
+ test.c:5:3: note: expanded from here
+ test.c:5:14: note: in expansion of macro 'SHIFTL'
+ test.c:8:3: note: expanded from here
+ test.c:8:3: note: in expansion of macro 'MULT2'
+ test.c:13:3: note: expanded from here
+
+ The part that goes from the third to the eighth line of this
+ diagnostic (the lines containing the 'note:' string) is called the
+ unwound macro expansion trace. That's the part generated by this
+ function.
+
+ If FIRST_EXP_POINT_MAP is non-null, *FIRST_EXP_POINT_MAP is set to
+ the map of the location in the source that first triggered the
+ macro expansion. This must be an ordinary map. */
+
+static void
+maybe_unwind_expanded_macro_loc (diagnostic_context *context,
+ diagnostic_info *diagnostic,
+ source_location where,
+ const struct line_map **first_exp_point_map)
+{
+ const struct line_map *map;
+ VEC(loc_map_pair,heap) *loc_vec = NULL;
+ unsigned ix;
+ loc_map_pair loc, *iter;
+
+ map = linemap_lookup (line_table, where);
+ if (!linemap_macro_expansion_map_p (map))
+ return;
+
+ /* Let's unwind the macros that got expanded and led to the token
+ which location is WHERE. We are going to store these macros into
+ LOC_VEC, so that we can later walk it at our convenience to
+ display a somewhat meaningful trace of the macro expansion
+ history to the user. Note that the first macro of the trace
+ (which is OPERATE in the example above) is going to be stored at
+ the beginning of LOC_VEC. */
+
+ do
+ {
+ loc.where = where;
+ loc.map = map;
+
+ VEC_safe_push (loc_map_pair, heap, loc_vec, &loc);
+
+ /* WHERE is the location of a token inside the expansion of a
+ macro. MAP is the map holding the locations of that macro
+ expansion. Let's get the location of the token inside the
+ context that triggered the expansion of this macro.
+ This is basically how we go "down" in the trace of macro
+ expansions that led to WHERE. */
+ where = linemap_unwind_toward_expansion (line_table, where, &map);
+ } while (linemap_macro_expansion_map_p (map));
+
+ if (first_exp_point_map)
+ *first_exp_point_map = map;
+
+ /* Walk LOC_VEC and print the macro expansion trace, unless the
+ first macro which expansion triggered this trace was expanded
+ inside a system header. */
+ if (!LINEMAP_SYSP (map))
+ FOR_EACH_VEC_ELT (loc_map_pair, loc_vec, ix, iter)
+ {
+ source_location resolved_def_loc = 0, resolved_exp_loc = 0;
+ diagnostic_t saved_kind;
+ const char *saved_prefix;
+ source_location saved_location;
+
+ /* Okay, now here is what we want. For each token resulting
+ from macro expansion we want to show: 1/ where in the
+ definition of the macro the token comes from; 2/ where the
+ macro got expanded. */
+
+ /* Resolve the location iter->where into the locus 1/ of the
+ comment above. */
+ resolved_def_loc =
+ linemap_resolve_location (line_table, iter->where,
+ LRK_MACRO_DEFINITION_LOCATION, NULL);
+
+ /* Resolve the location of the expansion point of the macro
+ which expansion gave the token represented by def_loc.
+ This is the locus 2/ of the earlier comment. */
+ resolved_exp_loc =
+ linemap_resolve_location (line_table,
+ MACRO_MAP_EXPANSION_POINT_LOCATION (iter->map),
+ LRK_MACRO_DEFINITION_LOCATION, NULL);
+
+ saved_kind = diagnostic->kind;
+ saved_prefix = context->printer->prefix;
+ saved_location = diagnostic->location;
+
+ diagnostic->kind = DK_NOTE;
+ diagnostic->location = resolved_def_loc;
+ pp_base_set_prefix (context->printer,
+ diagnostic_build_prefix (context,
+ diagnostic));
+ pp_newline (context->printer);
+ pp_printf (context->printer, "in expansion of macro '%s'",
+ linemap_map_get_macro_name (iter->map));
+ pp_destroy_prefix (context->printer);
+
+ diagnostic->location = resolved_exp_loc;
+ pp_base_set_prefix (context->printer,
+ diagnostic_build_prefix (context,
+ diagnostic));
+ pp_newline (context->printer);
+ pp_printf (context->printer, "expanded from here");
+ pp_destroy_prefix (context->printer);
+
+ diagnostic->kind = saved_kind;
+ diagnostic->location = saved_location;
+ context->printer->prefix = saved_prefix;
+ }
+
+ VEC_free (loc_map_pair, heap, loc_vec);
+}
+
+/* This is a diagnostic finalizer implementation that is aware of
+ virtual locations produced by libcpp.
+
+ It has to be called by the diagnostic finalizer of front ends that
+ uses libcpp and wish to get diagnostics involving tokens resulting
+ from macro expansion.
+
+ For a given location, if said location belongs to a token
+ resulting from a macro expansion, this starter prints the context
+ of the token. E.g, for multiply nested macro expansion, it
+ unwinds the nested macro expansions and prints them in a manner
+ that is similar to what is done for function call stacks, or
+ template instantiation contexts. */
+void
+virt_loc_aware_diagnostic_finalizer (diagnostic_context *context,
+ diagnostic_info *diagnostic)
+{
+ maybe_unwind_expanded_macro_loc (context, diagnostic,
+ diagnostic->location,
+ NULL);
}
OSDN Git Service
