From mboxrd@z Thu Jan  1 00:00:00 1970
From: Dibyendu Majumdar <mobile@majumdar.org.uk>
Subject: sparse-llvm incorrect handling of function pointers
Date: Fri, 10 Mar 2017 14:23:26 +0000
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To: Linux-Sparse <linux-sparse@vger.kernel.org>

Hi,

This example fails:

extern int (*f) (int);
int main(int argc, const char *argv[]) {
 if (f) {
  return (*f)(6);
 }
}

The linearized output is:

main:
.L0:
        <entry-point>
        load.64     %r1(f) <- 0[f]
        br          %r1(f), .L1, .L3
.L1:
        load        %r3 <- 0[%r1(f)]
        call.32     %r4 <- %r3, $6
        br          .L3
.L3:
        ret.32      %r4

It is the second load that is failing. Am investigating the cause - it
seems something to do with calc_memop_addr().

Regards
Dibyendu