Use _ instead of $ on Windows to avoid shell expansion issues.
Fixes
MOS_MIGRATED_REVID=143695463
@@ -1056,7 +1056,7 @@ string GetHashedBaseDir(const string& root, const string& hashable) {
static const char* alphabet
// Exactly 64 characters.
- = "abcdefghigklmnopqrstuvwxyzABCDEFGHIGKLMNOPQRSTUVWXYZ0123456789$-";
+ = "abcdefghigklmnopqrstuvwxyzABCDEFGHIGKLMNOPQRSTUVWXYZ0123456789_-";
// The length of the resulting filename (8 characters).
static const int filename_length = blaze_util::Md5Digest::kDigestLength / 2;
