From: Jim Meyering <meyer...@redhat.com>
Add comments so no one else will be tempted to reduce the scope
of this global variable.
Signed-off-by: Jim Meyering <meyer...@redhat.com>
---
tcg/tcg.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/tcg/tcg.c b/tcg/tcg.c
index ab589c7..2793fa6 100644
--- a/tcg/tcg.c
+++ b/tcg/tcg.c
@@ -2264,7 +2264,9 @@ void tcg_dump_info(FILE *f, fprintf_function cpu_fprintf)
(3) Call tcg_register_jit_int, with the constructed .debug_frame.
*/
-/* Begin GDB interface. THE FOLLOWING MUST MATCH GDB DOCS. */
+/* Begin GDB interface. THE FOLLOWING MUST MATCH GDB DOCS:
+ http://sourceware.org/gdb/onlinedocs/gdb/Declarations.html
+*/
typedef enum {
JIT_NOACTION = 0,
JIT_REGISTER_FN,
@@ -2291,8 +2293,10 @@ void __jit_debug_register_code(void)
asm("");
}
-/* Must statically initialize the version, because GDB may check
- the version before we can set it. */
+/* We must initialize the version this way, because GDB may check
+ the version before we can set it. This declaration must have
+ external scope. If it were "static", an aggressive compiler might
+ notice that we never read this symbol and remove it altogether. */
struct jit_descriptor __jit_debug_descriptor = { 1, 0, 0, 0 };
/* End GDB interface. */
--
1.7.10.2.552.gaa3bb87
