[Bug debug/102979] New: GCC gives wrong error for struct definitions without semicolon, despite G++ doing so

[konstantinua00 at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102979

Bug ID: 102979
   Summary: GCC gives wrong error for struct definitions without
semicolon, despite G++ doing so
   Product: gcc
   Version: 11.2.0
Status: UNCONFIRMED
  Severity: normal
  Priority: P3
 Component: debug
  Assignee: unassigned at gcc dot gnu.org
  Reporter: konstantinua00 at gmail dot com
  Target Milestone: ---

```
struct test{int i;}
```
https://godbolt.org/z/GEz56T7bT

Current error: "error: expected identifier or '(' at end of input" (points to
"test")

G++ on the other hand gives reasonable:
"error: expected ';' after struct definition"
https://godbolt.org/z/YGqvY7bsa

Is it possible to get G++'s error in GCC too?

[Bug debug/102978] New: Function/Struct declaration with absent semicolon that is put before including standard header results in wall of errors with no indication of the actual problem

[konstantinua00 at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102978

Bug ID: 102978
   Summary: Function/Struct declaration with absent semicolon that
is put before including standard header results in
wall of errors with no indication of the actual
problem
   Product: gcc
   Version: 11.2.0
Status: UNCONFIRMED
  Severity: normal
  Priority: P3
 Component: debug
  Assignee: unassigned at gcc dot gnu.org
  Reporter: konstantinua00 at gmail dot com
  Target Milestone: ---

```
void foo()
#include 
```
or
```
struct bar
#include 
```
as stated, give many useless errors.

example with : https://godbolt.org/z/KbrrszEWr  
less intimidating example with : https://godbolt.org/z/hxnxzqTcW
example with struct declaration: https://godbolt.org/z/nhTKc8cM9
happens in GCC with C std header too: https://godbolt.org/z/c6hMWexcW

Such situation happens when there're 2 user headers: first with missing
semicolon and second with new-in-TU std header.

G++(but not GCC) already notices missing semicolon on struct definitions and
GCC (but not G++) notices globals without one (due to typedef 
https://godbolt.org/z/44oYT1PKn), so maybe something can be done for
declarations too?

[Bug libstdc++/101870] New: std::lerp is missing Arithmetic overloads

[konstantinua00 at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101870

Bug ID: 101870
   Summary: std::lerp is missing Arithmetic overloads
   Product: gcc
   Version: 11.2.0
Status: UNCONFIRMED
  Severity: normal
  Priority: P3
 Component: libstdc++
  Assignee: unassigned at gcc dot gnu.org
  Reporter: konstantinua00 at gmail dot com
  Target Milestone: ---

According to C++20 standard paragraph 20.8.1.2, std::lerp is not an exception
to expansion of acceptable parameters to integral and mixed floating point
types.
I.e. overload 4) from https://en.cppreference.com/w/cpp/numeric/lerp is
missing.

Example code (compile with -std=c++20):

#include

int main()
{
std::lerp(int{},int{},int{});
std::lerp(float{}, double{}, (long double)0);
}

https://godbolt.org/z/3PqP9M4GE

Current behaviour:
Does not compile with: "error: call of overloaded 'lerp(int, int, int)' is
ambiguous" and "error: call of overloaded 'lerp(float, double, long double)' is
ambiguous".

Expected behaviour:
Compilation with no issues.