[Bug target/90867] [7/8/9/10 Regression] Multiplication or typecast of integer and double always zero when...

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90867

Richard Biener  changed:

   What|Removed |Added

   Target Milestone|7.5 |8.4

--- Comment #3 from Richard Biener  ---
The GCC 7 branch is being closed, re-targeting to GCC 8.4.

[Bug target/90867] [7/8/9/10 Regression] Multiplication or typecast of integer and double always zero when...

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90867

Richard Biener  changed:

   What|Removed |Added

 Target||x86_64-*-*, i?86-*-*
   Priority|P3  |P2
 Status|UNCONFIRMED |NEW
  Known to work||5.5.0
   Keywords||wrong-code
   Last reconfirmed||2019-06-13
  Component|c   |target
 Ever confirmed|0   |1
Summary|Multiplication or typecast  |[7/8/9/10 Regression]
   |of integer and double   |Multiplication or typecast
   |always zero when... |of integer and double
   ||always zero when...
   Target Milestone|--- |7.5
  Known to fail||6.4.0

--- Comment #2 from Richard Biener  ---
Confirmed when compiling with -march=native.  It seems to work with
-march=haswell or other specific archs.  Also fails with -mavx or even -msse2.

For some reason main() ends up with x87 math and bogus calling conventions.

Also:

> gcc-8 t.c -msse2 -fdump-tree-optimized -mfpmath=sse
t.c:16:1: warning: SSE instruction set disabled, using 387 arithmetics
 {
 ^

may hint at the underlying issue.  Worked in GCC 5.