[Infra] Resolve Crashlytics C warnings (#15059)

Author: ncooke3

Crashlytics/CHANGELOG.md

@@ -1,3 +1,6 @@
+# Unreleased
+- [fixed] Resolved compiler warnings related to constant definitions. (#15059)
+
 # 11.13.0
 - [fixed] Improved startup time by putting some initialization steps on a background. (#13675, #13232)
 

Crashlytics/Crashlytics/Helpers/FIRCLSFile.m

@@ -28,11 +28,21 @@
 
 #include <unistd.h>
 
-// uint64_t should only have max 19 chars in base 10, and less in base 16
-static const size_t FIRCLSUInt64StringBufferLength = 21;
-static const size_t FIRCLSStringBufferLength = 16;
 const size_t FIRCLSWriteBufferLength = 1000;
 
+/// Use an enum to define true compile-time integer constants. This prevents
+/// compiler warnings when these constants are used to declare array sizes.
+enum {
+  /// The buffer size needed to hold a 64-bit unsigned integer as a string.
+  /// The largest uint64_t value (18,446,744,073,709,551,615) has 20 digits.
+  /// An additional byte is required for the null terminator.
+  FIRCLSUInt64StringBufferLength = 21,
+
+  /// The size in bytes of a raw 128-bit UUID. This is used for buffers
+  /// holding the binary data, not a C-style string.
+  FIRCLSStringBufferLength = 16
+};
+
 static bool FIRCLSFileInit(
     FIRCLSFile* file, const char* path, int fdm, bool appendMode, bool bufferWrites);
 

Crashlytics/Shared/FIRCLSUUID.m

@@ -16,7 +16,14 @@
 
 #import "Crashlytics/Shared/FIRCLSByteUtility.h"
 
-static NSInteger const FIRCLSUUIDStringLength = 33;
+/// Use an enum to define a true compile-time integer constant. This prevents
+/// warning below where the constant is used to declare the size of an array.
+enum {
+  /// The buffer size needed to hold the hexadecimal string representation of a
+  /// 16-byte UUID. This accounts for 32 characters (2 for each byte) plus one
+  /// byte for the null terminator.
+  FIRCLSUUIDStringLength = (16 * 2) + 1
+};
 
 #pragma mark Public methods