Fixing bugs introduced by type puns passed through scanning methods, discovered by offsetting mps_ss_s from the beginning of scanstatestruct.

Adding a pseudo-target "find-puns" which, on FreeBSD mostly, prints useful warnings about strict aliasing rule violations.
Fixing more strict aliasing rule violations found by the above.

Copied from Perforce
 Change: 179358
 ServerID: perforce.ravenbrook.com

1 files changed, 3 insertions, 3 deletions

diff --git a/mps/code/root.c b/mps/code/root.c
index 9484c4bfa36..9ce385a124c 100644
--- a/mps/code/root.c
+++ b/mps/code/root.c
@@ -478,20 +478,20 @@ Res RootScan(ScanState ss, Root root)
     break;
 
     case RootFUN:
-    res = (*root->the.fun.scan)(ss, root->the.fun.p, root->the.fun.s);
+    res = (*root->the.fun.scan)(&ss->ss_s, root->the.fun.p, root->the.fun.s);
     if (res != ResOK)
       goto failScan;
     break;
 
     case RootREG:
-    res = (*root->the.reg.scan)(ss, root->the.reg.thread,
+    res = (*root->the.reg.scan)(&ss->ss_s, root->the.reg.thread,
                                 root->the.reg.p, root->the.reg.s);
     if (res != ResOK)
       goto failScan;
     break;
 
     case RootFMT:
-    res = (*root->the.fmt.scan)(ss, root->the.fmt.base, root->the.fmt.limit);
+    res = (*root->the.fmt.scan)(&ss->ss_s, root->the.fmt.base, root->the.fmt.limit);
     ss->scannedSize += AddrOffset(root->the.fmt.base, root->the.fmt.limit);
     if (res != ResOK)
       goto failScan;