CreateUninitializedVector was performing the following actions:
1. call StartVector.
2. call make_space, and set buf to point to the reserved space.
3. call EndVector.
The problem is that a call to EndVector can ultimately call make_space, which
if the buffer is full, will cause a reallocation, invalidating the value stored
in buf. So setting buf needs to be delayed until after EndVector.
The following code, when run under valgrind shows a write to free'd memory before
the change, but no such error after:
int main()
{
flatbuffers::FlatBufferBuilder fbb(128);
char *buf = nullptr;
fbb.CreateUninitializedVector(128, &buf);
*buf = 0;
}
To support the use case described in issue google/flatbuffers#3826, a new command line option --gen-name-strings
has been added, which will cause a static GetFullyQualifiedName function to be added
to the C++ output for tables/structs.
Nnamdi