[Bug c++/89285] New: ICE after casting the this pointer in the constructor in C++17 mode

[guus at debian dot org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89285

Bug ID: 89285
   Summary: ICE after casting the this pointer in the constructor
in C++17 mode
   Product: gcc
   Version: 8.2.0
Status: UNCONFIRMED
  Severity: normal
  Priority: P3
 Component: c++
  Assignee: unassigned at gcc dot gnu.org
  Reporter: guus at debian dot org
  Target Milestone: ---

Created attachment 45656
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=45656&action=edit
Minimal reproducer code

While developing some code that links nested struct variables together in a
linked list at compile time, I got an ICE when I modified my code to, instead
of
storing pointers in the linked list, stored relative offsets. It seems that the
ICE was triggered due to doing a reinterpret_cast(this) inside a
constructor, although I might be wrong about that.

GCC version: gcc (Debian 8.2.0-20) 8.2.0
System type: Debian GNU/Linux unstable on an AMD64 machine

> g++ -std=c++17 -c reproducer.cc
during RTL pass: expand
reproducer.cc: In function ‘void __static_initialization_and_destruction_0(int,
int)’:
reproducer.cc:11:43: internal compiler error: in expand_expr_real_1, at
expr.c:10043
   *child = reinterpret_cast(this) - reinterpret_cast(child);
~~~^
0x7f4478edc09a __libc_start_main
../csu/libc-start.c:308

[Bug c++/89285] ICE after casting the this pointer in the constructor in C++17 mode

[guus at debian dot org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89285

--- Comment #1 from Guus Sliepen  ---
Comment on attachment 45656
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=45656
Minimal reproducer code

The while-loop can be removed as well, and it will still give an ICE.

[Bug c++/87075] New: ICE when compiling the test suite of GLM 0.9.9.0

[guus at debian dot org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87075

Bug ID: 87075
   Summary: ICE when compiling the test suite of GLM 0.9.9.0
   Product: gcc
   Version: 8.2.0
Status: UNCONFIRMED
  Severity: normal
  Priority: P3
 Component: c++
  Assignee: unassigned at gcc dot gnu.org
  Reporter: guus at debian dot org
  Target Milestone: ---

When compiling the test suite of GLM 0.9.9.0, a header-only OpenGL mathematics
library, a compiler error occurs with GCC 7 and later, but it seems earlier
versions work fine. The attached dump is from 8.2.0 when compiling the test
suite. A minimal program to reproduce it, with the GLM 0.9.9.0 headers
installed, is:

#include 

using namespace glm;

int main() {
mat2 a(0,1,2,3); // GCC from trunk already fails here
mat2 b = matrixCompMult(a, a);
mat2 c = mat2(0,1,2,3); // no ICE on 8.2.0 for: mat2 c(0,1,2,3);
}

The error message when compiling this example with 8.2.0:

: In function 'int main()':
:8:26: internal compiler error: in gimplify_expr, at gimplify.c:12385
 mat2 c = mat2(0,1,2,3); // no ICE on 8.2.0 for: mat2 c(0,1,2,3);
  ^

The error message when compiling this example with trunk:

: In function 'int main()':
:6:19:   in 'constexpr' expansion of 'a.glm::mat<2, 2, float,
(glm::qualifier)0>::mat(0, 1, 2, 3)'
:6:19: internal compiler error: tree check: expected constructor, have
void_cst in cxx_eval_store_expression, at cp/constexpr.c:3785
6 | mat2 a(0,1,2,3); // GCC from trunk already fails here
  |   ^

Let me know if I can provide more help.

[Bug c++/87075] ICE when compiling the test suite of GLM 0.9.9.0

[guus at debian dot org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87075

Guus Sliepen  changed:

   What|Removed |Added

 CC||guus at debian dot org

--- Comment #1 from Guus Sliepen  ---
Created attachment 44585
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=44585&action=edit
GCC dump