Don't rely on nullptr deref recovery
Fixes this -fno-sanitize-recover=undefined fail,
/types/language: hb-common.cc:385:20: runtime error: member access within null pointer of type 'const struct hb_language_impl_t'
#0 0x4caa34 in hb_language_to_string /home/user/code/harfbuzz/src/hb-common.cc:385:20
#1 0x4c9be8 in test_types_language /home/user/code/harfbuzz/test/api/test-common.c:205:3
#2 0x7f9557e72f49 (/usr/lib/x86_64-linux-gnu/libglib-2.0.so.0+0x72f49)
#3 0x7f9557e72e7a (/usr/lib/x86_64-linux-gnu/libglib-2.0.so.0+0x72e7a)
#4 0x7f9557e73121 in g_test_run_suite (/usr/lib/x86_64-linux-gnu/libglib-2.0.so.0+0x73121)
#5 0x7f9557e73140 in g_test_run (/usr/lib/x86_64-linux-gnu/libglib-2.0.so.0+0x73140)
#6 0x4c88a3 in hb_test_run /home/user/code/harfbuzz/test/api/./hb-test.h:88:10
#7 0x4c88a3 in main /home/user/code/harfbuzz/test/api/test-common.c:224:10
#8 0x7f9556e64b96 in __libc_start_main /build/glibc-OTsEL5/glibc-2.27/csu/../csu/libc-start.c:310
#9 0x41e7d9 in _start (/home/user/code/harfbuzz/test/api/test-common+0x41e7d9)
diff --git a/src/hb-common.cc b/src/hb-common.cc
index 0720237..08ec04e 100644
--- a/src/hb-common.cc
+++ b/src/hb-common.cc
@@ -381,7 +381,8 @@
const char *
hb_language_to_string (hb_language_t language)
{
- /* This is actually nullptr-safe! */
+ if (!language) return nullptr;
+
return language->s;
}
