Re: [PATCH] c++/114409 - ANNOTATE_EXPR and templates

[Richard Biener <rguenther@suse.de>]

On Wed, 10 Apr 2024, Jakub Jelinek wrote:

> On Wed, Apr 10, 2024 at 06:43:02PM +0200, Richard Biener wrote:
> > The following fixes a mismatch in COMPOUND_EXPR handling in
> > tsubst_expr vs tsubst_stmt where the latter allows a stmt in
> > operand zero but the former doesn't.  This makes a difference
> > for the case at hand because when the COMPOUND_EXPR is wrapped
> > inside an ANNOTATE_EXPR it gets handled by tsubst_expr and when
> > not, tsubst_stmt successfully handles it and the contained
> > DECL_EXPR in operand zero.
> > 
> > The following makes handling of COMPOUND_EXPR in tsubst_expr
> > consistent with that of tsubst_stmt for the operand that doesn't
> > specify the result and thus the reason we choose either or the
> > other for substing.
> > 
> > Bootstrapped and tested on x86_64-unknown-linux-gnu, OK?
> > 
> > Thanks,
> > Richard.
> > 
> > 	PR c++/114409
> > gcc/cp/
> > 	* pt.cc (tsubst_expr): Recurse to COMPOUND_EXPR operand
> > 	zero using tsubst_stmt, when that returns NULL return
> > 	the subst operand one, mimicing what tsubst_stmt does.
> > 
> > gcc/testsuite/
> > 	* g++.dg/pr114409.C: New testcase.
> 
> I've posted https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114409#c16
> for this already and Jason agreed to that version, so I just have to test it
> tonight:
> https://gcc.gnu.org/pipermail/gcc-patches/2024-April/649165.html

Ah, I saw the bugzilla patches and wanted this version to be sent
because I think the COMPOUND_EXPR inconsistency is odd.  So Jason,
please still have a look, not necessarily because of the bug
which can be fixed in multiple ways but because of that COMPOUND_EXPR
handling oddity (there are already some cases in tsubst_expr that
explicitly recurse with tsubst_stmt).

Richard.

-- 
Richard Biener <rguenther@suse.de>
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