diff --git a/tools/kokoro/tests/test_kokoro_layer_options.cpp b/tools/kokoro/tests/test_kokoro_layer_options.cpp
index 7fdd8e520..533d0fef4 100644
--- a/tools/kokoro/tests/test_kokoro_layer_options.cpp
+++ b/tools/kokoro/tests/test_kokoro_layer_options.cpp
@@ -102,10 +102,19 @@ int main() {
             detail::KokoroLayerOptionsScope s(opts(true));
             snake1d_forward(x1.data(), 4, 1000, a.data());
         }
+        // Both paths round the final x + sin^2(a x) / a to float, so each
+        // can be up to half an ulp of the output away from the exact value.
+        // Subtract that one-ulp allowance, then scale by |a| so the result
+        // is in sin^2 units and comparable to the fast_sin2 bound.
         double e = 0;
         for (int c = 0; c < 4; ++c)
-            for (int t = 0; t < 1000; ++t)
-                e = std::max(e, std::fabs((double) x[c * 1000 + t] - x1[c * 1000 + t]) * std::fabs(a[c]));
+            for (int t = 0; t < 1000; ++t) {
+                const float r = x[c * 1000 + t];
+                const double ulp = (double) std::nextafter(std::fabs(r), INFINITY) - std::fabs(r);
+                const double d = std::fabs((double) r - x1[c * 1000 + t]);
+                e = std::max(e, std::max(0.0, d - ulp) * std::fabs(a[c]));
+            }
+        std::printf("snake1d fast vs libm: max excess over output rounding %.3g\n", e);
         CHECK(e < 1e-6, "snake mismatch %.3g", e);
     }
 
diff --git a/tools/misaki-g2p/src/espeak.cpp b/tools/misaki-g2p/src/espeak.cpp
index 338825995..2db51fc7f 100644
--- a/tools/misaki-g2p/src/espeak.cpp
+++ b/tools/misaki-g2p/src/espeak.cpp
@@ -270,6 +270,7 @@ u32 EspeakFallback::phonemize_line(const u32 & text) {
     return out;
 #else
     (void) text;
+    (void) data_dir_;
     return u32();
 #endif
 }
diff --git a/tools/misaki-g2p/src/lexicon.cpp b/tools/misaki-g2p/src/lexicon.cpp
index 5349048d8..459f2f45d 100644
--- a/tools/misaki-g2p/src/lexicon.cpp
+++ b/tools/misaki-g2p/src/lexicon.cpp
@@ -2,6 +2,7 @@
 // Reader for misaki-en-us.lex (written by convert_misaki_lexicon.py).
 #include "misaki-internal.h"
 
+#include <algorithm>
 #include <cerrno>
 #include <cstdio>
 #include <cstring>
@@ -124,7 +125,7 @@ std::unique_ptr<LexFile> LexFile::open(const std::string & path, std::string & e
 
 LexFile::~LexFile() {
 #if !defined(MISAKI_NO_MMAP)
-    if (mapped_ && base_) munmap((void *) base_, size_);
+    if (mapped_ && base_) munmap(const_cast<uint8_t *>(base_), size_);
 #endif
 }
 
diff --git a/tools/misaki-g2p/src/misaki-internal.h b/tools/misaki-g2p/src/misaki-internal.h
index 7d9d7d3d1..8324c3da5 100644
--- a/tools/misaki-g2p/src/misaki-internal.h
+++ b/tools/misaki-g2p/src/misaki-internal.h
@@ -156,7 +156,7 @@ class EspeakFallback {
     u32 phonemize_line(const u32 & text);
     // libespeak-ng is process-global: another handle may have re-initialised
     // it with a different data directory since this one was opened.
-    [[maybe_unused]] std::string data_dir_;
+    std::string data_dir_;
 };
 bool espeak_linked();
 
diff --git a/tools/misaki-g2p/src/tagger.cpp b/tools/misaki-g2p/src/tagger.cpp
index 9de6d6766..3110b8dba 100644
--- a/tools/misaki-g2p/src/tagger.cpp
+++ b/tools/misaki-g2p/src/tagger.cpp
@@ -9,6 +9,7 @@
 // so the rules aim at those decisions, not at full tagging accuracy.
 #include "misaki-internal.h"
 
+#include <algorithm>
 #include <unordered_map>
 #include <unordered_set>
 
diff --git a/tools/misaki-g2p/tests/test_agreement.cpp b/tools/misaki-g2p/tests/test_agreement.cpp
index 8a930d977..cbf052b4a 100644
--- a/tools/misaki-g2p/tests/test_agreement.cpp
+++ b/tools/misaki-g2p/tests/test_agreement.cpp
@@ -12,6 +12,7 @@
 #include "misaki-g2p.h"
 #include "misaki-internal.h"
 
+#include <algorithm>
 #include <cstdint>
 #include <cstdio>
 #include <cstring>
diff --git a/tools/parakeet/tests/test_parakeet_kernels.cpp b/tools/parakeet/tests/test_parakeet_kernels.cpp
index 903ba2d60..54d3ffae3 100644
--- a/tools/parakeet/tests/test_parakeet_kernels.cpp
+++ b/tools/parakeet/tests/test_parakeet_kernels.cpp
@@ -6,6 +6,7 @@
 #include "pk-ops.h"
 #include "pk-pool.h"
 
+#include <algorithm>
 #include <cmath>
 #include <cstdio>
 #include <cstring>
diff --git a/tools/parakeet/tools/parakeet-cli.cpp b/tools/parakeet/tools/parakeet-cli.cpp
index 3563da3cb..8487153b9 100644
--- a/tools/parakeet/tools/parakeet-cli.cpp
+++ b/tools/parakeet/tools/parakeet-cli.cpp
@@ -6,6 +6,7 @@
 #include "parakeet.h"
 #include "pk-wav.h"
 
+#include <algorithm>
 #include <chrono>
 #include <cstdio>
 #include <cstdlib>
diff --git a/tools/parakeet/tools/pk-wav.h b/tools/parakeet/tools/pk-wav.h
index ed1f9fc6e..3c4ceb15e 100644
--- a/tools/parakeet/tools/pk-wav.h
+++ b/tools/parakeet/tools/pk-wav.h
@@ -3,6 +3,7 @@
 // windowed-sinc resampler to 16 kHz.
 #pragma once
 
+#include <algorithm>
 #include <cmath>
 #include <cstdint>
 #include <cstdio>