[llvm-bugs] [Bug 42569] New: "ran out of registers" while building i386 linux kernel

[via llvm-bugs]

https://bugs.llvm.org/show_bug.cgi?id=42569

            Bug ID: 42569
           Summary: "ran out of registers" while building i386 linux
                    kernel
           Product: clang
           Version: trunk
          Hardware: PC
                OS: Linux
            Status: NEW
          Severity: enhancement
          Priority: P
         Component: -New Bugs
          Assignee: unassignedclangbugs at nondot.org
          Reporter: arnd at linaro.org
                CC: htmldeveloper at gmail.com, llvm-bugs at lists.llvm.org,
                    neeilans at live.com, richard-llvm at metafoo.co.uk

One file in the linux kernel produces an internal error from the register
allocator. I reduced the test case to this:

typedef int (*tune_freq_func_t)(int , void * tuneargs);
static struct {
  int power_up;
  int power_down;
  tune_freq_func_t fm_tune_freq;
  tune_freq_func_t am_tune_freq;
  int fm_rsq_status;
  int agc_status;
  int intb_pin_cfg;
} a[1];
int b, c;
int fn1(void) { return a[c].fm_tune_freq(b, fn1); }

$ clang-9 -m32 -mregparm=3 -O2 -fno-strict-overflow -c si476x-cmd.c
error: ran out of registers during register allocation
1 error generated.

See https://godbolt.org/z/aQ96HC

-- 
You are receiving this mail because:
You are on the CC list for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-bugs/attachments/20190710/0e7dafef/attachment.html>