Fix strlen() of unbound array undefined behavior
LLDB testsuite fails when built by GCC8 on:
LLDB :: SymbolFile/DWARF/find-basic-namespace.cpp
This is because this code in LLDB codebase has undefined behavior:
#include <algorithm>
#include <string.h>
// lldb/source/Plugins/ObjectFile/Mach-O/ObjectFileMachO.cpp:1731
static struct section_64 {
char sectname[16];
char segname[16];
} sect64 = { {'_','_','a','p','p','l','e','_','n','a','m','e','s','p','a','c'}, "__DWARF" };
int main() {
return std::min<size_t>(strlen(sect64.sectname), sizeof(sect64.sectname));
}
It has been discussed as a (false) bugreport to GCC:
wrong-code: LLDB testcase fails: SymbolFile/DWARF/find-basic-namespace.cpp
https://bugzilla.redhat.com/show_bug.cgi?id=1672436
Differential Revision: https://reviews.llvm.org/D57781
llvm-svn: 353280
diff --git a/lldb/source/Plugins/ObjectFile/Mach-O/ObjectFileMachO.cpp b/lldb/source/Plugins/ObjectFile/Mach-O/ObjectFileMachO.cpp
index afe3777..b4c320f 100644
--- a/lldb/source/Plugins/ObjectFile/Mach-O/ObjectFileMachO.cpp
+++ b/lldb/source/Plugins/ObjectFile/Mach-O/ObjectFileMachO.cpp
@@ -1609,8 +1609,7 @@
bool add_section = true;
bool add_to_unified = true;
ConstString const_segname(
- load_cmd.segname,
- std::min<size_t>(strlen(load_cmd.segname), sizeof(load_cmd.segname)));
+ load_cmd.segname, strnlen(load_cmd.segname, sizeof(load_cmd.segname)));
SectionSP unified_section_sp(
context.UnifiedList.FindSectionByName(const_segname));
@@ -1729,8 +1728,7 @@
if (add_section) {
ConstString section_name(
- sect64.sectname,
- std::min<size_t>(strlen(sect64.sectname), sizeof(sect64.sectname)));
+ sect64.sectname, strnlen(sect64.sectname, sizeof(sect64.sectname)));
if (!const_segname) {
// We have a segment with no name so we need to conjure up segments
// that correspond to the section's segname if there isn't already such