[PATCH] Fix infinite recursion bug at get_msymbol_address.

Ali Tamur via gdb-patches
2019-11-07T04:05:49Z

The patch 4b610737f0 seems to have introduced the possibility of infinite
recursion. I have encountered the problem while debugging a failing in-house
test. I am sorry, it is fairly difficult to reduce the test case (and I don't
understand most of what is going on) but the stack trace shows a call to
objfpy_add_separate_debug_file, which eventually causes
lookup_minimal_symbol_by_pc_name to be invoked, which calls get_msymbol_address.
Somehow lookup_minimal_symbol_linkage finds the same symbol and the function
calls itself with the same parameters. I don't know whether this should be
classified as 'it should never happen', but this simple patch makes the test
pass and should be harmless, I think.

gdb/ChangeLog

* symtab.c (get_msymbol_address): Guard against infinite recursion.
---
gdb/symtab.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gdb/symtab.c b/gdb/symtab.c
index 2c934b9c22..b231cc6e84 100644
--- a/gdb/symtab.c
+++ b/gdb/symtab.c
@@ -6328,7 +6328,7 @@ get_msymbol_address (struct objfile *objf, const struct minimal_symbol *minsym)
{
bound_minimal_symbol found
= lookup_minimal_symbol_linkage (linkage_name, objfile);
- if (found.minsym != nullptr)
+ if (found.minsym != nullptr && found.minsym != minsym)
return BMSYMBOL_VALUE_ADDRESS (found);
}
}
--
2.24.0.rc1.363.gb1bccd3e3d-goog