On Thu, 2018-04-26 at 15:53 -0400, Jason Merrill wrote:
> On Thu, Apr 26, 2018 at 3:45 AM, Richard Biener
> <richard.guent...@gmail.com> wrote:
> > On Wed, Apr 25, 2018 at 7:10 PM, Nathan Sidwell <nat...@acm.org>
> > wrote:
> > > On 04/25/2018 11:41 AM, David Malcolm wrote:
> > > >
> > > > Jason Turner's video C++ Weekly - Ep 112 - GCC's Leaky
> > > > Abstractions shows
> > > > two issues where g++ offers suggestions about implementation
> > > > details:
> > >
> > >
> > > > For the lambda capture case, there are multiple members:
> > > >
> > > > $9 = <function_decl 0x7ffff1a1dd00 __ct >
> > >
> > >
> > > These names have a space at the end, so the user cannot name
> > > them. We could
> > > move the space to the beginning, if that helps?
> >
> > I think compiler-generated entities that are not supposed to be
> > user-visible should be DECL_ARTIFICIAL.
>
> Agreed, add_capture should set that flag on the FIELD_DECLs.
I had tried flagging the lambda-captured vars as DECL_ARTIFICIAL,
but it lead to a "too many initializers" error from reshape_init,
so (before I saw your email), I tried the following approach: rather
than looking at underscores, it uses is_lambda_ignored_entity (similar
to qualify_lookup without LOOKUP_HIDDEN).
Successfully bootstrapped & regrtested on x86_64-pc-linux-gnu.
Do you want me to do the DECL_ARTIFICAL approach, or is this OK?
gcc/cp/ChangeLog:
PR c++/85515
* name-lookup.c (consider_binding_level): Skip compiler-generated
variables.
* search.c (lookup_field_fuzzy_info::fuzzy_lookup_field): Flatten
nested if statements into a series of rejection tests. Reject
lambda-ignored entities as suggestions.
gcc/testsuite/ChangeLog:
PR c++/85515
* g++.dg/pr85515-1.C: New test.
* g++.dg/pr85515-2.C: New test.
---
gcc/cp/name-lookup.c | 6 ++++++
gcc/cp/search.c | 13 ++++++++++---
gcc/testsuite/g++.dg/pr85515-1.C | 18 ++++++++++++++++++
gcc/testsuite/g++.dg/pr85515-2.C | 22 ++++++++++++++++++++++
4 files changed, 56 insertions(+), 3 deletions(-)
create mode 100644 gcc/testsuite/g++.dg/pr85515-1.C
create mode 100644 gcc/testsuite/g++.dg/pr85515-2.C
diff --git a/gcc/cp/name-lookup.c b/gcc/cp/name-lookup.c
index d2e5acb..a51cf1b 100644
--- a/gcc/cp/name-lookup.c
+++ b/gcc/cp/name-lookup.c
@@ -5860,6 +5860,12 @@ consider_binding_level (tree name, best_match <tree,
const char *> &bm,
&& DECL_ANTICIPATED (d))
continue;
+ /* Skip compiler-generated variables (e.g. __for_begin/__for_end
+ within range for). */
+ if (TREE_CODE (d) == VAR_DECL
+ && DECL_ARTIFICIAL (d))
+ continue;
+
tree suggestion = DECL_NAME (d);
if (!suggestion)
continue;
diff --git a/gcc/cp/search.c b/gcc/cp/search.c
index bfeaf2c..22c0492 100644
--- a/gcc/cp/search.c
+++ b/gcc/cp/search.c
@@ -1224,9 +1224,16 @@ lookup_field_fuzzy_info::fuzzy_lookup_field (tree type)
for (tree field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
{
- if (!m_want_type_p || DECL_DECLARES_TYPE_P (field))
- if (DECL_NAME (field))
- m_candidates.safe_push (DECL_NAME (field));
+ if (m_want_type_p && !DECL_DECLARES_TYPE_P (field))
+ continue;
+
+ if (!DECL_NAME (field))
+ continue;
+
+ if (is_lambda_ignored_entity (field))
+ continue;
+
+ m_candidates.safe_push (DECL_NAME (field));
}
}
diff --git a/gcc/testsuite/g++.dg/pr85515-1.C b/gcc/testsuite/g++.dg/pr85515-1.C
new file mode 100644
index 0000000..96f767d
--- /dev/null
+++ b/gcc/testsuite/g++.dg/pr85515-1.C
@@ -0,0 +1,18 @@
+// { dg-require-effective-target c++14 }
+
+void test_1 ()
+{
+ auto lambda = [val = 2](){};
+ lambda.val; // { dg-bogus "did you mean" }
+ // { dg-error "has no member named 'val'" "" { target *-*-* } .-1 }
+}
+
+int test_2 ()
+{
+ auto lambda = [val = 2](){ return val; };
+
+ // TODO: should we issue an error for the following assignment?
+ lambda.__val = 4;
+
+ return lambda();
+}
diff --git a/gcc/testsuite/g++.dg/pr85515-2.C b/gcc/testsuite/g++.dg/pr85515-2.C
new file mode 100644
index 0000000..621ddb8
--- /dev/null
+++ b/gcc/testsuite/g++.dg/pr85515-2.C
@@ -0,0 +1,22 @@
+// { dg-require-effective-target c++11 }
+
+void test_1 ()
+{
+ int arr[] = {1, 2, 3, 4, 5};
+ for (const auto v: arr) {
+ _forbegin; // { dg-bogus "suggested alternative" }
+ // { dg-error "'_forbegin' was not declared in this scope" "" { target
*-*-*} .-1 }
+ }
+}
+
+int test_2 ()
+{
+ int arr[] = {1, 2, 3, 4, 5};
+ int sum = 0;
+ for (const auto v: arr) {
+ sum += v;
+ // TODO: should we issue an error for the following assignment?
+ __for_begin = __for_end;
+ }
+ return sum;
+}
--
1.8.5.3
