On 4/10/24 13:10, Richard Biener wrote:
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).
The difference between tsubst_stmt and tsubst_expr handling of
COMPOUND_EXPR seems consistent with the general difference between the
two functions, so I think this change isn't needed. The two existing
uses of tsubst_stmt in tsubst_expr are statement-expressions (for the
substatement) and transactions (strangely, non-statement transactions
are handled in tsubst_stmt).
Jason
