diff --git a/libc/arch-x86/bionic/__libc_init_sysinfo.cpp b/libc/arch-x86/bionic/__libc_init_sysinfo.cpp
index 5c44b4e..db931d1 100644
--- a/libc/arch-x86/bionic/__libc_init_sysinfo.cpp
+++ b/libc/arch-x86/bionic/__libc_init_sysinfo.cpp
@@ -37,8 +37,8 @@
 }
 
 __LIBC_HIDDEN__ void __libc_init_sysinfo() {
-  bool dummy;
-  __libc_sysinfo = reinterpret_cast<void*>(__bionic_getauxval(AT_SYSINFO, dummy));
+  bool unused;
+  __libc_sysinfo = reinterpret_cast<void*>(__bionic_getauxval(AT_SYSINFO, &unused));
 }
 
 // TODO: lose this function and just access __libc_sysinfo directly.
diff --git a/libc/bionic/getauxval.cpp b/libc/bionic/getauxval.cpp
index d6f75f8..a3c6b19 100644
--- a/libc/bionic/getauxval.cpp
+++ b/libc/bionic/getauxval.cpp
@@ -37,20 +37,20 @@
 
 // This function needs to be safe to call before TLS is set up, so it can't
 // access errno or the stack protector.
-__LIBC_HIDDEN__ unsigned long __bionic_getauxval(unsigned long type, bool& exists) {
+__LIBC_HIDDEN__ unsigned long __bionic_getauxval(unsigned long type, bool* exists) {
   for (ElfW(auxv_t)* v = __libc_shared_globals()->auxv; v->a_type != AT_NULL; ++v) {
     if (v->a_type == type) {
-      exists = true;
+      *exists = true;
       return v->a_un.a_val;
     }
   }
-  exists = false;
+  *exists = false;
   return 0;
 }
 
 extern "C" unsigned long getauxval(unsigned long type) {
   bool exists;
-  unsigned long result = __bionic_getauxval(type, exists);
+  unsigned long result = __bionic_getauxval(type, &exists);
   if (!exists) errno = ENOENT;
   return result;
 }
diff --git a/libc/bionic/libc_init_common.cpp b/libc/bionic/libc_init_common.cpp
index 1ede969..f1350d5 100644
--- a/libc/bionic/libc_init_common.cpp
+++ b/libc/bionic/libc_init_common.cpp
@@ -359,10 +359,8 @@
   Dtor* fini_array = reinterpret_cast<Dtor*>(array);
   const Dtor minus1 = reinterpret_cast<Dtor>(static_cast<uintptr_t>(-1));
 
-  // Sanity check - first entry must be -1.
-  if (array == nullptr || fini_array[0] != minus1) {
-    return;
-  }
+  // Validity check: the first entry must be -1.
+  if (array == nullptr || fini_array[0] != minus1) return;
 
   // Skip over it.
   fini_array += 1;
@@ -373,15 +371,9 @@
     ++count;
   }
 
-  // Now call each destructor in reverse order.
+  // Now call each destructor in reverse order, ignoring any -1s.
   while (count > 0) {
     Dtor dtor = fini_array[--count];
-
-    // Sanity check, any -1 in the list is ignored.
-    if (dtor == minus1) {
-      continue;
-    }
-
-    dtor();
+    if (dtor != minus1) dtor();
   }
 }
diff --git a/libc/bionic/pthread_attr.cpp b/libc/bionic/pthread_attr.cpp
index 1551c1f..89aa289 100644
--- a/libc/bionic/pthread_attr.cpp
+++ b/libc/bionic/pthread_attr.cpp
@@ -192,7 +192,8 @@
     return errno;
   }
 
-  // If the current RLIMIT_STACK is RLIM_INFINITY, only admit to an 8MiB stack for sanity's sake.
+  // If the current RLIMIT_STACK is RLIM_INFINITY, only admit to an 8MiB stack
+  // in case callers such as ART take infinity too literally.
   if (stack_limit.rlim_cur == RLIM_INFINITY) {
     stack_limit.rlim_cur = 8 * 1024 * 1024;
   }
diff --git a/libc/bionic/pthread_create.cpp b/libc/bionic/pthread_create.cpp
index d4a8bef..c528105 100644
--- a/libc/bionic/pthread_create.cpp
+++ b/libc/bionic/pthread_create.cpp
@@ -350,7 +350,7 @@
   return 0;
 }
 
-// A dummy start routine for pthread_create failures where we've created a thread but aren't
+// A no-op start routine for pthread_create failures where we've created a thread but aren't
 // going to run user code on it. We swap out the user's start routine for this and take advantage
 // of the regular thread teardown to free up resources.
 static void* __do_nothing(void*) {
diff --git a/libc/bionic/sysinfo.cpp b/libc/bionic/sysinfo.cpp
index 1d1070e..7ab8e9e 100644
--- a/libc/bionic/sysinfo.cpp
+++ b/libc/bionic/sysinfo.cpp
@@ -38,9 +38,10 @@
 
 static bool __matches_cpuN(const char* s) {
   // The %c trick is to ensure that we have the anchored match "^cpu[0-9]+$".
+  // We can't use %*c because the return value is how many were *assigned*.
   unsigned cpu;
-  char dummy;
-  return (sscanf(s, "cpu%u%c", &cpu, &dummy) == 1);
+  char unused;
+  return (sscanf(s, "cpu%u%c", &cpu, &unused) == 1);
 }
 
 int get_nprocs_conf() {
diff --git a/libc/include/nl_types.h b/libc/include/nl_types.h
index 622880a..1c80e4e 100644
--- a/libc/include/nl_types.h
+++ b/libc/include/nl_types.h
@@ -32,7 +32,7 @@
  * @file nl_types.h
  * @brief Message catalogs.
  *
- * Android offers a dummy implementation of these functions to ease porting of historical software.
+ * Android offers a no-op implementation of these functions to ease porting of historical software.
  */
 
 #include <sys/cdefs.h>
diff --git a/libc/private/bionic_auxv.h b/libc/private/bionic_auxv.h
index 8e33c1c..9d2cfdd 100644
--- a/libc/private/bionic_auxv.h
+++ b/libc/private/bionic_auxv.h
@@ -30,4 +30,4 @@
 
 #include <sys/cdefs.h>
 
-__LIBC_HIDDEN__ unsigned long __bionic_getauxval(unsigned long type, bool& exists);
+__LIBC_HIDDEN__ unsigned long __bionic_getauxval(unsigned long type, bool* exists);
diff --git a/libc/stdio/local.h b/libc/stdio/local.h
index 1ecf122..12f3bf5 100644
--- a/libc/stdio/local.h
+++ b/libc/stdio/local.h
@@ -259,7 +259,7 @@
 size_t parsefloat(FILE*, char*, char*);
 size_t wparsefloat(FILE*, wchar_t*, wchar_t*);
 
-// Sanity check a FILE* for nullptr, so we can emit a message while crashing
+// Check a FILE* isn't nullptr, so we can emit a message while crashing
 // instead of doing a blind null-dereference.
 #define CHECK_FP(fp) \
   if (fp == nullptr) __fortify_fatal("%s: null FILE*", __FUNCTION__)
diff --git a/libc/stdio/stdio.cpp b/libc/stdio/stdio.cpp
index a0b4219..afc2c48 100644
--- a/libc/stdio/stdio.cpp
+++ b/libc/stdio/stdio.cpp
@@ -1026,9 +1026,9 @@
   __check_count("vsnprintf", "size", n);
 
   // Stdio internals do not deal correctly with zero length buffer.
-  char dummy;
+  char one_byte_buffer[1];
   if (n == 0) {
-    s = &dummy;
+    s = one_byte_buffer;
     n = 1;
   }