| Message ID | 20170912060003.32378-1-derodat@adacore.com |
|---|---|
| State | New |
| Headers | show |
| Series | [PR82155] Fix crash in dwarf2out_abstract_function | expand |
On Tue, Sep 12, 2017 at 8:00 AM, Pierre-Marie de Rodat <derodat@adacore.com> wrote: > Hello, > > This patch is an attempt to fix the crash reported in PR82155. > > When generating a C++ class method for a class that is itself nested in > a class method, dwarf2out_early_global_decl currently leaves the > existing context DIE as it is if it already exists. However, it is > possible that this call happens at a point where this context DIE is > just a declaration that is itself not located in its own context. > > From there, if dwarf2out_early_global_decl is not called on any of the > FUNCTION_DECL in the context chain, DIEs will be left badly scoped and > some (such as the nested method) will be removed by the type pruning > machinery. As a consequence, dwarf2out_abstract_function will will > crash when called on the corresponding DECL because it asserts that the > DECL has a DIE. > > This patch fixes this crash making dwarf2out_early_global_decl process > context DIEs the same way we process abstract origins for FUNCTION_DECL: > if the corresponding DIE exists but is only a declaration, call > dwarf2out_decl anyway on it so that it is turned into a more complete > DIE and so that it is relocated in the proper context. > > Bootstrapped and regtested on x86_64-linux. The crash this addresses is > present both on trunk and on the gcc-7 branch: I suggest we commit this > patch on both branches. Ok to commit? Thank you in advance! Ok for trunk and gcc-7 branch after a while. Thanks, Richard. > gcc/ > > PR debug/82155 > * dwarf2out.c (dwarf2out_early_global_decl): Call dwarf2out_decl > on the FUNCTION_DECL function context if it has a DIE that is a > declaration. > > gcc/testsuite/ > > * g++.dg/pr82155.C: New testcase. > --- > gcc/dwarf2out.c | 10 ++++++++-- > gcc/testsuite/g++.dg/pr82155.C | 36 ++++++++++++++++++++++++++++++++++++ > 2 files changed, 44 insertions(+), 2 deletions(-) > create mode 100644 gcc/testsuite/g++.dg/pr82155.C > > diff --git a/gcc/dwarf2out.c b/gcc/dwarf2out.c > index 00d6d951ba3..4cfc9c186af 100644 > --- a/gcc/dwarf2out.c > +++ b/gcc/dwarf2out.c > @@ -25500,10 +25500,16 @@ dwarf2out_early_global_decl (tree decl) > so that all nested DIEs are generated at the proper scope in the > first shot. */ > tree context = decl_function_context (decl); > - if (context != NULL && lookup_decl_die (context) == NULL) > + if (context != NULL) > { > + dw_die_ref context_die = lookup_decl_die (context); > current_function_decl = context; > - dwarf2out_decl (context); > + > + /* Avoid emitting DIEs multiple times, but still process CONTEXT > + enough so that it lands in its own context. This avoids type > + pruning issues later on. */ > + if (context_die == NULL || is_declaration_die (context_die)) > + dwarf2out_decl (context); > } > > /* Emit an abstract origin of a function first. This happens > diff --git a/gcc/testsuite/g++.dg/pr82155.C b/gcc/testsuite/g++.dg/pr82155.C > new file mode 100644 > index 00000000000..75d9b615f39 > --- /dev/null > +++ b/gcc/testsuite/g++.dg/pr82155.C > @@ -0,0 +1,36 @@ > +/* { dg-do compile { target c++11 } } */ > +/* { dg-options "-g -O2" } */ > + > +template <typename a> struct b { a c; }; > +template <typename d> struct e { d *operator->(); }; > +template <typename d> class h { > +public: > + typedef e<d> ag; > +}; > +class i { > +protected: > + i(int); > +}; > +class j { > + virtual void k(int) = 0; > + > +public: > + int f; > + void l() { k(f); } > +}; > +struct m : i { > + int cn; > + m() : i(cn) { > + struct n : j { > + n() {} > + void k(int) {} > + }; > + } > +}; > +struct o { > + o() { > + for (h<b<b<j *>>>::ag g;;) > + g->c.c->l(); > + } > +}; > +void fn1() { o(); } > -- > 2.14.1 >
On 09/25/2017 01:54 PM, Richard Biener wrote:
> Ok for trunk and gcc-7 branch after a while.
Thank you, Richard! Committed on trunk as 253147; I’ll wait at least one
week to revisit the gcc-7 branch commit.
Hello Richard,
On 09/25/2017 01:54 PM, Richard Biener wrote:
> Ok for trunk and gcc-7 branch after a while.
Is it still okay to commit to gcc-7, now?
On Wed, Nov 15, 2017 at 10:11 AM, Pierre-Marie de Rodat <derodat@adacore.com> wrote: > Hello Richard, > > On 09/25/2017 01:54 PM, Richard Biener wrote: >> >> Ok for trunk and gcc-7 branch after a while. > > Is it still okay to commit to gcc-7, now? Yes. Richard. > -- > Pierre-Marie de Rodat
On 11/15/2017 12:16 PM, Richard Biener wrote: >> Is it still okay to commit to gcc-7, now? > > Yes. Done. Thank you!
diff --git a/gcc/dwarf2out.c b/gcc/dwarf2out.c index 00d6d951ba3..4cfc9c186af 100644 --- a/gcc/dwarf2out.c +++ b/gcc/dwarf2out.c @@ -25500,10 +25500,16 @@ dwarf2out_early_global_decl (tree decl) so that all nested DIEs are generated at the proper scope in the first shot. */ tree context = decl_function_context (decl); - if (context != NULL && lookup_decl_die (context) == NULL) + if (context != NULL) { + dw_die_ref context_die = lookup_decl_die (context); current_function_decl = context; - dwarf2out_decl (context); + + /* Avoid emitting DIEs multiple times, but still process CONTEXT + enough so that it lands in its own context. This avoids type + pruning issues later on. */ + if (context_die == NULL || is_declaration_die (context_die)) + dwarf2out_decl (context); } /* Emit an abstract origin of a function first. This happens diff --git a/gcc/testsuite/g++.dg/pr82155.C b/gcc/testsuite/g++.dg/pr82155.C new file mode 100644 index 00000000000..75d9b615f39 --- /dev/null +++ b/gcc/testsuite/g++.dg/pr82155.C @@ -0,0 +1,36 @@ +/* { dg-do compile { target c++11 } } */ +/* { dg-options "-g -O2" } */ + +template <typename a> struct b { a c; }; +template <typename d> struct e { d *operator->(); }; +template <typename d> class h { +public: + typedef e<d> ag; +}; +class i { +protected: + i(int); +}; +class j { + virtual void k(int) = 0; + +public: + int f; + void l() { k(f); } +}; +struct m : i { + int cn; + m() : i(cn) { + struct n : j { + n() {} + void k(int) {} + }; + } +}; +struct o { + o() { + for (h<b<b<j *>>>::ag g;;) + g->c.c->l(); + } +}; +void fn1() { o(); }