[PATCH] Allow value repeat operator on references

Hannes Domani
2024-02-09T13:05:42Z

Currently it's not possible to use the value repeat operator on references:
```
print ((int &) v_int_array_init[0])@2
Only values in memory can be extended with '@'.
```

This seems like an unnecessary restriction, since it also prevents
its use on iterators (which was the original reported problem):
```
(gdb) p *it@2
Only values in memory can be extended with '@'.
```

So this converts any references to the referenced value in value_repeat,
making this possible:
```
print ((int &) v_int_array_init[0])@2
$1 = {10, 20}
(gdb) p *it@2
$2 = {1, 2}
```
---
gdb/testsuite/gdb.base/exprs.exp | 1 +
gdb/valops.c | 2 ++
2 files changed, 3 insertions(+)

diff --git a/gdb/testsuite/gdb.base/exprs.exp b/gdb/testsuite/gdb.base/exprs.exp
index 239cdce8dc2..0f8c53bc716 100644
--- a/gdb/testsuite/gdb.base/exprs.exp
+++ b/gdb/testsuite/gdb.base/exprs.exp
@@ -259,6 +259,7 @@ gdb_test {print *v_int_array_init@2} { = \{10, 20\}}
gdb_test {print v_int_array_init[0]@1} { = \{10\}}
gdb_test {print v_int_array_init[0]@2} { = \{10, 20\}}
gdb_test {print v_int_array_init[1]@1} { = \{20\}}
+gdb_test {print ((int &) v_int_array_init[0])@2} { = \{10, 20\}}

# gdb's {} extension
gdb_test_no_output "set variable v_short_array\[0\] = 42"
diff --git a/gdb/valops.c b/gdb/valops.c
index e2694f0c32b..399d0f109e1 100644
--- a/gdb/valops.c
+++ b/gdb/valops.c
@@ -1349,6 +1349,8 @@ value_repeat (struct value *arg1, int count)
{
struct value *val;

+ arg1 = coerce_ref (arg1);
+
if (arg1->lval () != lval_memory)
error (_("Only values in memory can be extended with '@'."));
if (count < 1)
--
2.35.1