Re: [PATCH 3/6] Emit macro expansion related diagnostics

[Richard Guenther <richard dot guenther at gmail dot com>]

On Mon, Oct 17, 2011 at 11:57 AM, Dodji Seketeli <dodji@redhat.com> wrote:
> In this third instalment the diagnostic machinery -- when faced with
> the virtual location of a token resulting from macro expansion -- uses
> the new linemap APIs to unwind the stack of macro expansions that led
> to that token and emits a [hopefully] more useful message than what we
> have today.
>
> diagnostic_report_current_module has been slightly changed to use the
> location given by client code instead of the global input_location
> variable. ?This results in more precise diagnostic locations in
> general but then the patch adjusts some C++ tests which output changed
> as a result of this.
>
> Three new regression tests have been added.
>
> The mandatory screenshot goes like this:
>
> [dodji@adjoa gcc]$ 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 ? ?}
>
> [dodji@adjoa gcc]$ ./cc1 -quiet -ftrack-macro-expansion test.c
> test.c: In function 'g':
> test.c:5:14: erreur: 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

This broke bootstrap on x86_64-linux.

/space/rguenther/src/svn/trunk/libcpp/line-map.c: In function
'source_location linemap_macro_map_loc_to_exp_point(const line_map*,
source_location)':
/space/rguenther/src/svn/trunk/libcpp/line-map.c:628:12: error:
variable 'token_no' set but not used [-Werror=unused-but-set-variable]
cc1plus: all warnings being treated as errors

make[3]: *** [line-map.o] Error 1


> gcc/ChangeLog
> 2011-10-15 ?Tom Tromey ?<tromey@redhat.com>
> ? ? ? ? ? ?Dodji Seketeli ?<dodji@redhat.com>
>
> ? ? ? ?* gcc/diagnostic.h (diagnostic_report_current_module): Add a
> ? ? ? ?location parameter.
> ? ? ? ?* diagnostic.c (diagnostic_report_current_module): Add a location
> ? ? ? ?parameter to the function definition. ?Use it instead of
> ? ? ? ?input_location. ?Resolve the virtual location rather than just
> ? ? ? ?looking up its map and risking to touch a resulting macro map.
> ? ? ? ?(default_diagnostic_starter): Pass the relevant diagnostic
> ? ? ? ?location to diagnostic_report_current_module.
> ? ? ? ?* tree-diagnostic.c (maybe_unwind_expanded_macro_loc): New.
> ? ? ? ?(virt_loc_aware_diagnostic_finalizer): Likewise.
> ? ? ? ?(diagnostic_report_current_function): Pass the
> ? ? ? ?relevant location to diagnostic_report_current_module.
> ? ? ? ?* tree-diagnostic.h (virt_loc_aware_diagnostic_finalizer): Declare
> ? ? ? ?new function.
> ? ? ? ?* toplev.c (general_init): By default, use the new
> ? ? ? ?virt_loc_aware_diagnostic_finalizer as diagnostic finalizer.
> ? ? ? ?* Makefile.in: Add vec.h dependency to tree-diagnostic.c.
>
> gcc/cp/ChangeLog
> 2011-10-15 ?Tom Tromey ?<tromey@redhat.com>
> ? ? ? ? ? ?Dodji Seketeli ?<dodji@redhat.com>
>
> ? ? ? ?* error.c (cp_diagnostic_starter): Pass the relevant location to
> ? ? ? ?diagnostic_report_current_module.
> ? ? ? ?(cp_diagnostic_finalizer): Call virt_loc_aware_diagnostic_finalizer.
>
> gcc/testsuite/ChangeLog
> 2011-10-15 ?Tom Tromey ?<tromey@redhat.com>
> ? ? ? ? ? ?Dodji Seketeli ?<dodji@redhat.com>
>
> ? ? ? ?* lib/prune.exp (prune_gcc_output): ?Prune output referring to
> ? ? ? ?included files.
> ? ? ? ?* gcc.dg/cpp/macro-exp-tracking-1.c: New test.
> ? ? ? ?* gcc.dg/cpp/macro-exp-tracking-2.c: Likewise.
> ? ? ? ?* gcc.dg/cpp/macro-exp-tracking-3.c: Likewise.
> ? ? ? ?* gcc.dg/cpp/pragma-diagnostic-2.c: Likewise.
>
> ---
> ?gcc/ChangeLog ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? | ? 21 +++
> ?gcc/Makefile.in ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? | ? ?3 +-
> ?gcc/cp/ChangeLog ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?| ? ?7 +
> ?gcc/cp/error.c ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?| ? ?5 +-
> ?gcc/diagnostic.c ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?| ? 13 +-
> ?gcc/diagnostic.h ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?| ? ?2 +-
> ?gcc/testsuite/ChangeLog ? ? ? ? ? ? ? ? ? ? ? ? | ? 10 ++
> ?gcc/testsuite/gcc.dg/cpp/macro-exp-tracking-1.c | ? 21 +++
> ?gcc/testsuite/gcc.dg/cpp/macro-exp-tracking-2.c | ? 21 +++
> ?gcc/testsuite/gcc.dg/cpp/macro-exp-tracking-3.c | ? 14 ++
> ?gcc/testsuite/gcc.dg/cpp/macro-exp-tracking-4.c | ? 14 ++
> ?gcc/testsuite/gcc.dg/cpp/pragma-diagnostic-2.c ?| ? 34 +++++
> ?gcc/testsuite/lib/prune.exp ? ? ? ? ? ? ? ? ? ? | ? ?1 +
> ?gcc/toplev.c ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?| ? ?3 +
> ?gcc/tree-diagnostic.c ? ? ? ? ? ? ? ? ? ? ? ? ? | ?182 ++++++++++++++++++++++-
> ?gcc/tree-diagnostic.h ? ? ? ? ? ? ? ? ? ? ? ? ? | ? ?3 +-
> ?16 files changed, 343 insertions(+), 11 deletions(-)
> ?create mode 100644 gcc/testsuite/gcc.dg/cpp/macro-exp-tracking-1.c
> ?create mode 100644 gcc/testsuite/gcc.dg/cpp/macro-exp-tracking-2.c
> ?create mode 100644 gcc/testsuite/gcc.dg/cpp/macro-exp-tracking-3.c
> ?create mode 100644 gcc/testsuite/gcc.dg/cpp/macro-exp-tracking-4.c
> ?create mode 100644 gcc/testsuite/gcc.dg/cpp/pragma-diagnostic-2.c
>
> diff --git a/gcc/Makefile.in b/gcc/Makefile.in
> index baec5fe..70dc0b8 100644
> --- a/gcc/Makefile.in
> +++ b/gcc/Makefile.in
> @@ -2805,7 +2805,8 @@ tree-pretty-print.o : tree-pretty-print.c $(CONFIG_H) $(SYSTEM_H) \
> ? ?$(TM_H) coretypes.h tree-iterator.h $(SCEV_H) langhooks.h \
> ? ?$(TREE_PASS_H) value-prof.h output.h tree-pretty-print.h
> ?tree-diagnostic.o : tree-diagnostic.c $(CONFIG_H) $(SYSTEM_H) coretypes.h \
> - ? $(TREE_H) $(DIAGNOSTIC_H) tree-diagnostic.h langhooks.h $(LANGHOOKS_DEF_H)
> + ? $(TREE_H) $(DIAGNOSTIC_H) tree-diagnostic.h langhooks.h $(LANGHOOKS_DEF_H) \
> + ? $(VEC_H)
> ?fold-const.o : fold-const.c $(CONFIG_H) $(SYSTEM_H) coretypes.h $(TM_H) \
> ? ?$(TREE_H) $(FLAGS_H) $(DIAGNOSTIC_CORE_H) $(HASHTAB_H) $(EXPR_H) $(RTL_H) \
> ? ?$(GGC_H) $(TM_P_H) langhooks.h $(MD5_H) intl.h $(TARGET_H) \
> diff --git a/gcc/cp/error.c b/gcc/cp/error.c
> index 4d12a0d..c7c4525 100644
> --- a/gcc/cp/error.c
> +++ b/gcc/cp/error.c
> @@ -2768,7 +2768,7 @@ static void
> ?cp_diagnostic_starter (diagnostic_context *context,
> ? ? ? ? ? ? ? ? ? ? ? diagnostic_info *diagnostic)
> ?{
> - ?diagnostic_report_current_module (context);
> + ?diagnostic_report_current_module (context, diagnostic->location);
> ? cp_print_error_function (context, diagnostic);
> ? maybe_print_instantiation_context (context);
> ? maybe_print_constexpr_context (context);
> @@ -2778,8 +2778,9 @@ cp_diagnostic_starter (diagnostic_context *context,
>
> ?static void
> ?cp_diagnostic_finalizer (diagnostic_context *context,
> - ? ? ? ? ? ? ? ? ? ? ? ?diagnostic_info *diagnostic ATTRIBUTE_UNUSED)
> + ? ? ? ? ? ? ? ? ? ? ? ?diagnostic_info *diagnostic)
> ?{
> + ?virt_loc_aware_diagnostic_finalizer (context, diagnostic);
> ? pp_base_destroy_prefix (context->printer);
> ?}
>
> diff --git a/gcc/diagnostic.c b/gcc/diagnostic.c
> index b46eb35..a8c0e66 100644
> --- a/gcc/diagnostic.c
> +++ b/gcc/diagnostic.c
> @@ -255,9 +255,9 @@ diagnostic_action_after_output (diagnostic_context *context,
> ?}
>
> ?void
> -diagnostic_report_current_module (diagnostic_context *context)
> +diagnostic_report_current_module (diagnostic_context *context, location_t where)
> ?{
> - ?const struct line_map *map;
> + ?const struct line_map *map = NULL;
>
> ? if (pp_needs_newline (context->printer))
> ? ? {
> @@ -265,10 +265,13 @@ diagnostic_report_current_module (diagnostic_context *context)
> ? ? ? pp_needs_newline (context->printer) = false;
> ? ? }
>
> - ?if (input_location <= BUILTINS_LOCATION)
> + ?if (where <= BUILTINS_LOCATION)
> ? ? return;
>
> - ?map = linemap_lookup (line_table, input_location);
> + ?linemap_resolve_location (line_table, where,
> + ? ? ? ? ? ? ? ? ? ? ? ? ? LRK_MACRO_DEFINITION_LOCATION,
> + ? ? ? ? ? ? ? ? ? ? ? ? ? &map);
> +
> ? if (map && diagnostic_last_module_changed (context, map))
> ? ? {
> ? ? ? diagnostic_set_last_module (context, map);
> @@ -301,7 +304,7 @@ void
> ?default_diagnostic_starter (diagnostic_context *context,
> ? ? ? ? ? ? ? ? ? ? ? ? ? ?diagnostic_info *diagnostic)
> ?{
> - ?diagnostic_report_current_module (context);
> + ?diagnostic_report_current_module (context, diagnostic->location);
> ? pp_set_prefix (context->printer, diagnostic_build_prefix (context,
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?diagnostic));
> ?}
> diff --git a/gcc/diagnostic.h b/gcc/diagnostic.h
> index 8074354..4b1265b 100644
> --- a/gcc/diagnostic.h
> +++ b/gcc/diagnostic.h
> @@ -253,7 +253,7 @@ extern diagnostic_context *global_dc;
> ?/* Diagnostic related functions. ?*/
> ?extern void diagnostic_initialize (diagnostic_context *, int);
> ?extern void diagnostic_finish (diagnostic_context *);
> -extern void diagnostic_report_current_module (diagnostic_context *);
> +extern void diagnostic_report_current_module (diagnostic_context *, location_t);
>
> ?/* Force diagnostics controlled by OPTIDX to be kind KIND. ?*/
> ?extern diagnostic_t diagnostic_classify_diagnostic (diagnostic_context *,
> diff --git a/gcc/testsuite/gcc.dg/cpp/macro-exp-tracking-1.c b/gcc/testsuite/gcc.dg/cpp/macro-exp-tracking-1.c
> new file mode 100644
> index 0000000..d975c8c
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/cpp/macro-exp-tracking-1.c
> @@ -0,0 +1,21 @@
> +/*
> + ? { dg-options "-ftrack-macro-expansion=1" }
> + ? { dg-do compile }
> +*/
> +
> +#define OPERATE(OPRD1, OPRT, OPRD2) \
> +do \
> +{ \
> + ?OPRD1 OPRT OPRD2; /* { dg-message "expansion" }*/ ? ? ? \
> +} while (0)
> +
> +#define SHIFTL(A,B) \
> + ?OPERATE (A,<<,B) /* { dg-message "expanded|expansion" } */
> +
> +void
> +foo ()
> +{
> + ?SHIFTL (0.1,0.2); /* { dg-message "expanded" } */
> +}
> +
> +/* { dg-error "invalid operands" "" { target *-*-* } 13 } */
> diff --git a/gcc/testsuite/gcc.dg/cpp/macro-exp-tracking-2.c b/gcc/testsuite/gcc.dg/cpp/macro-exp-tracking-2.c
> new file mode 100644
> index 0000000..684af4c
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/cpp/macro-exp-tracking-2.c
> @@ -0,0 +1,21 @@
> +/*
> + ? { dg-options "-ftrack-macro-expansion=1" }
> + ? { dg-do compile }
> +*/
> +
> +#define OPERATE(OPRD1, OPRT, OPRD2) \
> + OPRD1 OPRT OPRD2; ? ? ? ? ? ? /* { dg-message "expansion" } */
> +
> +#define SHIFTL(A,B) \
> + ?OPERATE (A,<<,B) /* { dg-message "expanded|expansion" } */
> +
> +#define MULT(A) \
> + ?SHIFTL (A,1) ? ? ? ? ? ? ? ? /* { dg-message "expanded|expansion" } */
> +
> +void
> +foo ()
> +{
> + ?MULT (1.0); ? ? ? ? ? ? ? ? ?/* { dg-message "expanded" } */
> +}
> +
> +/* { dg-error "invalid operands to binary <<" "" { target *-*-* } { 10 } } */
> diff --git a/gcc/testsuite/gcc.dg/cpp/macro-exp-tracking-3.c b/gcc/testsuite/gcc.dg/cpp/macro-exp-tracking-3.c
> new file mode 100644
> index 0000000..119053e
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/cpp/macro-exp-tracking-3.c
> @@ -0,0 +1,14 @@
> +/*
> + ?{ dg-options "-fshow-column -ftrack-macro-expansion=1" }
> + ?{ dg-do compile }
> + */
> +
> +#define SQUARE(A) A * A ? ? ? ? ? ? ? ?/* { dg-message "expansion" } */
> +
> +void
> +foo()
> +{
> + ?SQUARE (1 << 0.1); ? ? ? ? ? /* { dg-message "expanded" } */
> +}
> +
> +/* { dg-error "16:invalid operands to binary <<" "" {target *-*-* } { 11 } } */
> diff --git a/gcc/testsuite/gcc.dg/cpp/macro-exp-tracking-4.c b/gcc/testsuite/gcc.dg/cpp/macro-exp-tracking-4.c
> new file mode 100644
> index 0000000..1f9fe6a
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/cpp/macro-exp-tracking-4.c
> @@ -0,0 +1,14 @@
> +/*
> + ?{ dg-options "-fshow-column -ftrack-macro-expansion=2" }
> + ?{ dg-do compile }
> + */
> +
> +#define SQUARE(A) A * A ? ? ? ? ? ? ? ?/* { dg-message "expansion" } */
> +
> +void
> +foo()
> +{
> + ?SQUARE (1 << 0.1); ? ? ? ? ? /* { dg-message "expanded" } */
> +}
> +
> +/* { dg-error "13:invalid operands to binary <<" "" { target *-*-* } { 11 } } */
> diff --git a/gcc/testsuite/gcc.dg/cpp/pragma-diagnostic-2.c b/gcc/testsuite/gcc.dg/cpp/pragma-diagnostic-2.c
> new file mode 100644
> index 0000000..7ab95b0
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/cpp/pragma-diagnostic-2.c
> @@ -0,0 +1,34 @@
> +/*
> + ?{ dg-options "-Wuninitialized -ftrack-macro-expansion=2" }
> + ?{ dg-do compile }
> +*/
> +
> +void f (unsigned);
> +
> +#define CODE_WITH_WARNING \
> + ?int a; /* { dg-message "expansion|declared here" } */ ?\
> + ?f (a) ? ? ? ? /* { dg-message "expansion" } */
> +
> +#pragma GCC diagnostic ignored "-Wuninitialized"
> +
> +void
> +g (void)
> +{
> + ?CODE_WITH_WARNING;
> +}
> +
> +#pragma GCC diagnostic push
> +
> +#pragma GCC diagnostic error "-Wuninitialized"
> +
> +void
> +h (void)
> +{
> + ?CODE_WITH_WARNING; ? ? ? ? ? /* { dg-message "expanded" } */
> +}
> +
> +/*
> + ?{ dg-message "some warnings being treated as errors" "" {target *-*-*} 0 }
> +*/
> +
> +/* { dg-error "uninitialized" "" { target *-*-* } { 10 } } */
> diff --git a/gcc/testsuite/lib/prune.exp b/gcc/testsuite/lib/prune.exp
> index 4683f93..09d2581 100644
> --- a/gcc/testsuite/lib/prune.exp
> +++ b/gcc/testsuite/lib/prune.exp
> @@ -29,6 +29,7 @@ proc prune_gcc_output { text } {
> ? ? regsub -all "(^|\n)collect: re(compiling|linking)\[^\n\]*" $text "" text
> ? ? regsub -all "(^|\n)Please submit.*instructions\[^\n\]*" $text "" text
> ? ? regsub -all "(^|\n)\[0-9\]\[0-9\]* errors\." $text "" text
> + ? ?regsub -all "(^|\n)(In file included|\[ \]+from)\[^\n\]*" $text "" text
>
> ? ? # Ignore informational notes.
> ? ? regsub -all "(^|\n)\[^\n\]*: note: \[^\n\]*" $text "" text
> diff --git a/gcc/toplev.c b/gcc/toplev.c
> index ab6b5a4..0188755 100644
> --- a/gcc/toplev.c
> +++ b/gcc/toplev.c
> @@ -1171,6 +1171,9 @@ general_init (const char *argv0)
> ? ? ?can give warnings and errors. ?*/
> ? diagnostic_initialize (global_dc, N_OPTS);
> ? diagnostic_starter (global_dc) = default_tree_diagnostic_starter;
> + ?/* By default print macro expansion contexts in the diagnostic
> + ? ? finalizer -- for tokens resulting from macro macro expansion. ?*/
> + ?diagnostic_finalizer (global_dc) = virt_loc_aware_diagnostic_finalizer;
> ? /* Set a default printer. ?Language specific initializations will
> ? ? ?override it later. ?*/
> ? pp_format_decoder (global_dc->printer) = &default_tree_printer;
> diff --git a/gcc/tree-diagnostic.c b/gcc/tree-diagnostic.c
> index b456a2a..53b350b 100644
> --- a/gcc/tree-diagnostic.c
> +++ b/gcc/tree-diagnostic.c
> @@ -28,6 +28,7 @@ along with GCC; see the file COPYING3. ?If not see
> ?#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. ?*/
> @@ -35,7 +36,7 @@ void
> ?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);
> ?}
>
> @@ -47,3 +48,182 @@ default_tree_diagnostic_starter (diagnostic_context *context,
> ? 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_t;
> +
> +DEF_VEC_O (loc_t);
> +DEF_VEC_ALLOC_O (loc_t, 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_t,heap) *loc_vec = NULL;
> + ?unsigned ix;
> + ?loc_t 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_t, 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_t, 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_t, 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);
> +}
> diff --git a/gcc/tree-diagnostic.h b/gcc/tree-diagnostic.h
> index 7d88089..6b8e8e6 100644
> --- a/gcc/tree-diagnostic.h
> +++ b/gcc/tree-diagnostic.h
> @@ -52,5 +52,6 @@ along with GCC; see the file COPYING3. ?If not see
> ?void default_tree_diagnostic_starter (diagnostic_context *, diagnostic_info *);
> ?extern void diagnostic_report_current_function (diagnostic_context *,
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?diagnostic_info *);
> -
> +void virt_loc_aware_diagnostic_finalizer (diagnostic_context *,
> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? diagnostic_info *);
> ?#endif /* ! GCC_TREE_DIAGNOSTIC_H */
> --
> 1.7.6.4
>
>