Thanks for the help. I had started working on this back in July, ran into trouble, and put it on hold until recently, which explains why my code was out-of-date. I still have some compilation problems, but with some brute-force hacking, I got it to build. Here are the changes.

You can see that in ldv42000hle.cpp, I needed to make some casts to disambiguate the parameter to signbit(). Not sure why MSVC did not like this, but the MinGW compiler didn't care.

In the other files, there were some more complex compiler errors. I just commented out the code (!) and hope I don't run into it.

Thanks for the help!

Code
diff --git a/src/devices/bus/mtu130/datamover.cpp b/src/devices/bus/mtu130/datamover.cpp
index 3b5d8f33ee0..aeaedcc5f46 100644
--- a/src/devices/bus/mtu130/datamover.cpp
+++ b/src/devices/bus/mtu130/datamover.cpp
@@ -3,6 +3,7 @@

 // Datamover - 68K-based extension board

+#include "emu.h"
 #include "datamover.h"

 DEFINE_DEVICE_TYPE(MTU130_DATAMOVER0, mtu130_datamover0_device, "datamover0", "Datamover")
diff --git a/src/devices/machine/ldv4200hle.cpp b/src/devices/machine/ldv4200hle.cpp
index db8f86a2a03..cebdd5739c2 100644
--- a/src/devices/machine/ldv4200hle.cpp
+++ b/src/devices/machine/ldv4200hle.cpp
@@ -801,7 +801,7 @@ TIMER_CALLBACK_MEMBER(pioneer_ldv4200hle_device::process_vbi_data)
                                int32_t old_delta = (int32_t)m_mark_frame - (int32_t)old_frame;
                                int32_t curr_delta = (int32_t)m_mark_frame - (int32_t)m_curr_frame;
                                LOGMASKED(LOG_STOPS, "%s: Stop Mark is currently %d, old frame is %d, current frame is %d, old delta %d, curr delta %d\n", machine().describe_context(), m_mark_frame, old_frame, m_curr_frame, old_delta, curr_delta);
-                               if (curr_delta == 0 || std::signbit(old_delta) != std::signbit(curr_delta))
+                               if (curr_delta == 0 || std::signbit((double)old_delta) != std::signbit((double)curr_delta))
                                {
                                        m_mark_frame = ~uint32_t(0);
                                        if (is_cav_disc())
@@ -919,7 +919,7 @@ int32_t pioneer_ldv4200hle_device::player_update(const vbi_metadata &vbi, int fi
                        int32_t jump_frame = (int32_t)m_curr_frame + elapsed_tracks;
                        int32_t curr_delta = (int32_t)m_mark_frame - (int32_t)m_curr_frame;
                        int32_t next_delta = (int32_t)m_mark_frame - (int32_t)jump_frame;
-                       if (std::signbit(curr_delta) != std::signbit(next_delta))
+                       if (std::signbit((double)curr_delta) != std::signbit((double)next_delta))
                        {
                                elapsed_tracks = curr_delta;
                        }
diff --git a/src/mame/nintendo/vsnes.cpp b/src/mame/nintendo/vsnes.cpp
index 7044c909e7c..90dc1fc3000 100644
--- a/src/mame/nintendo/vsnes.cpp
+++ b/src/mame/nintendo/vsnes.cpp
@@ -949,9 +949,12 @@ void vs_dual_state::vsdual_vrom_banking(u8 data)
        // switch vrom
        m_chr_banks[Side]->set_entry(BIT(data, 2));

+#if 0
+       // SFR Removed
        // bit 1 ( data & 2 ) triggers irq on the other cpu
        auto cpu = (Side == SUB) ? m_maincpu : m_subcpu;
        cpu->set_input_line(0, (data & 2) ? CLEAR_LINE : ASSERT_LINE);
+#endif

        // move along
        vsnes_in0_w<Side>(data);
diff --git a/src/mame/sony/news_r4k.cpp b/src/mame/sony/news_r4k.cpp
index a83e7c3f468..caece8d1b6a 100644
--- a/src/mame/sony/news_r4k.cpp
+++ b/src/mame/sony/news_r4k.cpp
@@ -442,11 +442,14 @@ void news_r4k_state::machine_common(machine_config &config)
                                escc1_int_status = status ? 0x8 : 0x0; // guess
                        });

+#if 0
+       // SFR Removed
        CXD8452AQ(config, m_sonic3, 0);
        m_sonic3->set_addrmap(0, &news_r4k_state::sonic3_map);
        m_sonic3->irq_out().set(FUNC(news_r4k_state::irq_w<irq0_number::SONIC>));
        m_sonic3->set_bus(m_cpu, 0);
        m_sonic3->set_apbus_address_translator(FUNC(news_r4k_state::apbus_virt_to_phys));
+#endif

        // TODO: actual clock frequency - there is a 20MHz crystal nearby on the board, but traces need to be confirmed
        DP83932C(config, m_sonic, 20'000'000);
@@ -476,10 +479,13 @@ void news_r4k_state::machine_common(machine_config &config)
                        [this] ()
                        { return uint32_t(m_fdc->dma_r()); });

+#if 0
+       // SFR Removed
        DMAC3(config, m_dmac, 0);
        m_dmac->set_apbus_address_translator(FUNC(news_r4k_state::apbus_virt_to_phys));
        m_dmac->set_bus(m_cpu, 0);
        m_dmac->irq_out().set(FUNC(news_r4k_state::irq_w<DMAC>));
+#endif

        NSCSI_BUS(config, m_scsibus0);
        NSCSI_BUS(config, m_scsibus1);