Prefer C++ notation over C

nullptr instead of 0 and nothing instead of void for function arguments is preferred.

absl/base/internal/low_level_alloc.cc

@@ -550,7 +550,7 @@ static void *DoAllocWithArena(size_t request, LowLevelAlloc::Arena *arena) {
       size_t new_pages_size = RoundUp(req_rnd, arena->pagesize * 16);
       void *new_pages;
 #ifdef _WIN32
-      new_pages = VirtualAlloc(0, new_pages_size,
+      new_pages = VirtualAlloc(nullptr, new_pages_size,
                                MEM_RESERVE | MEM_COMMIT, PAGE_READWRITE);
       ABSL_RAW_CHECK(new_pages != nullptr, "VirtualAlloc failed");
 #else

absl/base/internal/sysinfo.cc

@@ -159,7 +159,7 @@ static double GetNominalCPUFrequency() {
     DWORD type = 0;
     DWORD data = 0;
     DWORD data_size = sizeof(data);
-    auto result = RegQueryValueExA(key, "~MHz", 0, &type,
+    auto result = RegQueryValueExA(key, "~MHz", nullptr, &type,
                                    reinterpret_cast<LPBYTE>(&data), &data_size);
     RegCloseKey(key);
     if (result == ERROR_SUCCESS && type == REG_DWORD &&

absl/debugging/internal/symbolize.h

@@ -115,7 +115,7 @@ bool RemoveSymbolDecorator(int ticket);
 
 // Remove all installed decorators.  Returns true if successful, false if
 // symbolization is currently in progress.
-bool RemoveAllSymbolDecorators(void);
+bool RemoveAllSymbolDecorators();
 
 // Registers an address range to a file mapping.
 //