diff --git a/tools/llvm-cov/CoverageReport.cpp b/tools/llvm-cov/CoverageReport.cpp
index 94071b7367e..7ac9355fa50 100644
--- a/tools/llvm-cov/CoverageReport.cpp
+++ b/tools/llvm-cov/CoverageReport.cpp
@@ -110,17 +110,17 @@ static raw_ostream::Colors determineCoveragePercentageColor(const T &Info) {
 
 void CoverageReport::render(const FileCoverageSummary &File, raw_ostream &OS) {
   OS << column(File.Name, FileReportColumns[0], Column::LeftTrim)
-     << format("%*zd", FileReportColumns[1], File.RegionCoverage.NumRegions);
+     << format("%*u", FileReportColumns[1], (unsigned)File.RegionCoverage.NumRegions);
   Options.colored_ostream(OS, File.RegionCoverage.isFullyCovered()
                                   ? raw_ostream::GREEN
                                   : raw_ostream::RED)
-      << format("%*zd", FileReportColumns[2], File.RegionCoverage.NotCovered);
+      << format("%*u", FileReportColumns[2], (unsigned)File.RegionCoverage.NotCovered);
   Options.colored_ostream(OS,
                           determineCoveragePercentageColor(File.RegionCoverage))
       << format("%*.2f", FileReportColumns[3] - 1,
                 File.RegionCoverage.getPercentCovered()) << '%';
-  OS << format("%*zd", FileReportColumns[4],
-               File.FunctionCoverage.NumFunctions);
+  OS << format("%*u", FileReportColumns[4],
+               (unsigned)File.FunctionCoverage.NumFunctions);
   Options.colored_ostream(
       OS, determineCoveragePercentageColor(File.FunctionCoverage))
       << format("%*.2f", FileReportColumns[5] - 1,
@@ -131,24 +131,24 @@ void CoverageReport::render(const FileCoverageSummary &File, raw_ostream &OS) {
 void CoverageReport::render(const FunctionCoverageSummary &Function,
                             raw_ostream &OS) {
   OS << column(Function.Name, FunctionReportColumns[0], Column::RightTrim)
-     << format("%*zd", FunctionReportColumns[1],
-               Function.RegionCoverage.NumRegions);
+     << format("%*u", FunctionReportColumns[1],
+               (unsigned)Function.RegionCoverage.NumRegions);
   Options.colored_ostream(OS, Function.RegionCoverage.isFullyCovered()
                                   ? raw_ostream::GREEN
                                   : raw_ostream::RED)
-      << format("%*zd", FunctionReportColumns[2],
-                Function.RegionCoverage.NotCovered);
+      << format("%*u", FunctionReportColumns[2],
+                (unsigned)Function.RegionCoverage.NotCovered);
   Options.colored_ostream(
       OS, determineCoveragePercentageColor(Function.RegionCoverage))
       << format("%*.2f", FunctionReportColumns[3] - 1,
                 Function.RegionCoverage.getPercentCovered()) << '%';
-  OS << format("%*zd", FunctionReportColumns[4],
-               Function.LineCoverage.NumLines);
+  OS << format("%*u", FunctionReportColumns[4],
+               (unsigned)Function.LineCoverage.NumLines);
   Options.colored_ostream(OS, Function.LineCoverage.isFullyCovered()
                                   ? raw_ostream::GREEN
                                   : raw_ostream::RED)
-      << format("%*zd", FunctionReportColumns[5],
-                Function.LineCoverage.NotCovered);
+      << format("%*u", FunctionReportColumns[5],
+                (unsigned)Function.LineCoverage.NotCovered);
   Options.colored_ostream(
       OS, determineCoveragePercentageColor(Function.LineCoverage))
       << format("%*.2f", FunctionReportColumns[6] - 1,