In the testcases with the PR, we have a bit of type punning going on,
*(int *) &s2.f = 0;
s2 = s1;
which SRA trasforms to
# DEBUG s2 => 0
MEM[(int *)&s2] = 0;
# DEBUG s2 => s1$f_7
# DEBUG s2$g => s1$g_6
s2 ={v} {CLOBBER};
Note that it has chosen not to expand s1.f like s1.g, but to expand that field
as the type-punned integer. Which means that "s2 => s1$f_7" has mismatched
types across lhs and rhs: SI => SF. Which understandibly ICEs during rtl
expansion.
I'm not really sure how this is avoided for the actual code generation, but
this minimal patch (aka hack) simply drops the debug info to avoid the ICE.
Thoughts on how this might really be solved?
r~
diff --git a/gcc/testsuite/gcc.dg/debug/pr59776.c
b/gcc/testsuite/gcc.dg/debug/pr59776.c
new file mode 100644
index 0000000..245c3d7
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/debug/pr59776.c
@@ -0,0 +1,12 @@
+/* { dg-do compile } */
+
+struct S { float f, g; };
+
+void
+sub_ (struct S *p)
+{
+ struct S s1, s2;
+ s1 = *p;
+ *(int *) &s2.f = 0;
+ s2 = s1;
+}
diff --git a/gcc/tree-sra.c b/gcc/tree-sra.c
index 4992b4c..f9ff0a4 100644
--- a/gcc/tree-sra.c
+++ b/gcc/tree-sra.c
@@ -2950,9 +2950,15 @@ load_assign_lhs_subreplacements (struct access *lacc,
struct access *top_racc,
lacc);
else
drhs = NULL_TREE;
- ds = gimple_build_debug_bind (get_access_replacement (lacc),
- drhs, gsi_stmt (*old_gsi));
- gsi_insert_after (new_gsi, ds, GSI_NEW_STMT);
+
+ // ??? Can this type mismatch only happen with debuginfo,
+ // or can it happen with real code as well?
+ if (drhs && types_compatible_p (lacc->type, TREE_TYPE (drhs)))
+ {
+ ds = gimple_build_debug_bind (get_access_replacement (lacc),
+ drhs, gsi_stmt (*old_gsi));
+ gsi_insert_after (new_gsi, ds, GSI_NEW_STMT);
+ }
}
}
