QMap C++ initializer list slow with clang

I have a large static QMap which is used with C++ initializer lists:

static const QMap<quint64, EcoInfo> ECOINFOS {
{Q_UINT64_C(0x8da7a73e5fdd72dc), {"A00", ""}},
{Q_UINT64_C(0xe89f55cd52014748), {"A00", ""}},
{Q_UINT64_C(0xeb16d4aa32ce7438), {"A00", "Van't Kruijs Opening"}},
{Q_UINT64_C(0xaec84ba6d432356e), {"A00", ""}},
{Q_UINT64_C(0x2df2e8f47b022952), {"A00", ""}},
{Q_UINT64_C(0x30e16e80c6e1f31a), {"A00", "Sargossa Opening"}},
{Q_UINT64_C(0xe57697cefee41181), {"A00", "Grob's Attack"}},
{Q_UINT64_C(0xeccee3b4b02790b8), {"A00", "Sokolsky Opening"}},
...

}

Approximately there are 1200 entries.

When compiling this with clang on OS X (Xcode 8, which should correspond to Apple LLVM version 8.0.0 (clang-800.0.XX) this is incredibly slow (doesn't finish). Cutting down the QMap to a few hundred lines eventually compiles.

Older versions (i.e. build chain using gcc) works fine.