diff --git a/compiler-rt/lib/asan/asan_descriptions.cpp b/compiler-rt/lib/asan/asan_descriptions.cpp
index ef6f3e0a096f..05a277cfa0a8 100644
--- a/compiler-rt/lib/asan/asan_descriptions.cpp
+++ b/compiler-rt/lib/asan/asan_descriptions.cpp
@@ -245,11 +245,11 @@ static void PrintAccessAndVarIntersection(const StackVarDescr &var, uptr addr,
   InternalScopedString str;
   str.AppendF("    [%zd, %zd)", var.beg, var_end);
   // Render variable name.
-  str.AppendF(" '");
+  str.Append(" '");
   for (uptr i = 0; i < var.name_len; ++i) {
     str.AppendF("%c", var.name_pos[i]);
   }
-  str.AppendF("'");
+  str.Append("'");
   if (var.line > 0) {
     str.AppendF(" (line %zd)", var.line);
   }
@@ -260,7 +260,7 @@ static void PrintAccessAndVarIntersection(const StackVarDescr &var, uptr addr,
     str.AppendF("%s <== Memory access at offset %zd %s this variable%s\n",
                 d.Location(), addr, pos_descr, d.Default());
   } else {
-    str.AppendF("\n");
+    str.Append("\n");
   }
   Printf("%s", str.data());
 }
diff --git a/compiler-rt/lib/hwasan/hwasan_report.cpp b/compiler-rt/lib/hwasan/hwasan_report.cpp
index 12a4fa47f215..c3d260d1a61f 100644
--- a/compiler-rt/lib/hwasan/hwasan_report.cpp
+++ b/compiler-rt/lib/hwasan/hwasan_report.cpp
@@ -388,7 +388,7 @@ static void PrintTagInfoAroundAddr(uptr addr, uptr num_rows,
       print_tag(s, row + i);
       s.Append(row + i == addr ? "]" : " ");
     }
-    s.AppendF("\n");
+    s.Append("\n");
   }
 }
 
@@ -418,10 +418,10 @@ static void PrintTagsAroundAddr(uptr addr, GetTag get_tag,
                              tag_t short_tag = get_short_tag(tag_addr);
                              s.AppendF("%02x", short_tag);
                            } else {
-                             s.AppendF("..");
+                             s.Append("..");
                            }
                          });
-  s.AppendF(
+  s.Append(
       "See "
       "https://clang.llvm.org/docs/"
       "HardwareAssistedAddressSanitizerDesign.html#short-granules for a "
@@ -947,16 +947,16 @@ TailOverwrittenReport::~TailOverwrittenReport() {
 
   InternalScopedString s;
   u8 *tail = tail_copy;
-  s.AppendF("Tail contains: ");
-  for (uptr i = 0; i < kShadowAlignment - tail_size; i++) s.AppendF(".. ");
+  s.Append("Tail contains: ");
+  for (uptr i = 0; i < kShadowAlignment - tail_size; i++) s.Append(".. ");
   for (uptr i = 0; i < tail_size; i++) s.AppendF("%02x ", tail[i]);
-  s.AppendF("\n");
-  s.AppendF("Expected:      ");
-  for (uptr i = 0; i < kShadowAlignment - tail_size; i++) s.AppendF(".. ");
+  s.Append("\n");
+  s.Append("Expected:      ");
+  for (uptr i = 0; i < kShadowAlignment - tail_size; i++) s.Append(".. ");
   for (uptr i = 0; i < tail_size; i++) s.AppendF("%02x ", actual_expected[i]);
-  s.AppendF("\n");
-  s.AppendF("               ");
-  for (uptr i = 0; i < kShadowAlignment - tail_size; i++) s.AppendF("   ");
+  s.Append("\n");
+  s.Append("               ");
+  for (uptr i = 0; i < kShadowAlignment - tail_size; i++) s.Append("   ");
   for (uptr i = 0; i < tail_size; i++)
     s.AppendF("%s ", actual_expected[i] != tail[i] ? "^^" : "  ");
 
diff --git a/compiler-rt/lib/memprof/memprof_descriptions.cpp b/compiler-rt/lib/memprof/memprof_descriptions.cpp
index 48b74b6bc87f..4fbe2943e653 100644
--- a/compiler-rt/lib/memprof/memprof_descriptions.cpp
+++ b/compiler-rt/lib/memprof/memprof_descriptions.cpp
@@ -51,7 +51,7 @@ void DescribeThread(MemprofThreadContext *context) {
   InternalScopedString str;
   str.AppendF("Thread %s", MemprofThreadIdAndName(context).c_str());
   if (context->parent_tid == kInvalidTid) {
-    str.AppendF(" created by unknown thread\n");
+    str.Append(" created by unknown thread\n");
     Printf("%s", str.data());
     return;
   }
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_stacktrace_libcdep.cpp b/compiler-rt/lib/sanitizer_common/sanitizer_stacktrace_libcdep.cpp
index 561eae9ab780..1a0e00d5d5af 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_stacktrace_libcdep.cpp
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_stacktrace_libcdep.cpp
@@ -63,7 +63,7 @@ class StackTraceTextPrinter {
 
     if (dedup_frames_-- > 0) {
       if (dedup_token_->length())
-        dedup_token_->AppendF("--");
+        dedup_token_->Append("--");
       if (stack->info.function)
         dedup_token_->Append(stack->info.function);
     }
@@ -99,7 +99,7 @@ void StackTrace::PrintTo(InternalScopedString *output) const {
                                 output, &dedup_token);
 
   if (trace == nullptr || size == 0) {
-    output->AppendF("    <empty stack>\n\n");
+    output->Append("    <empty stack>\n\n");
     return;
   }
 
@@ -111,7 +111,7 @@ void StackTrace::PrintTo(InternalScopedString *output) const {
   }
 
   // Always add a trailing empty line after stack trace.
-  output->AppendF("\n");
+  output->Append("\n");
 
   // Append deduplication token, if non-empty.
   if (dedup_token.length())
@@ -198,7 +198,7 @@ void __sanitizer_symbolize_pc(uptr pc, const char *fmt, char *out_buf,
   StackTraceTextPrinter printer(fmt, '\0', &output, nullptr);
   if (!printer.ProcessAddressFrames(pc)) {
     output.clear();
-    output.AppendF("<can't symbolize>");
+    output.Append("<can't symbolize>");
   }
   CopyStringToBuffer(output, out_buf, out_buf_size);
 }
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_stacktrace_printer.cpp b/compiler-rt/lib/sanitizer_common/sanitizer_stacktrace_printer.cpp
index 748d832ccc21..b23796fccf6e 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_stacktrace_printer.cpp
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_stacktrace_printer.cpp
@@ -152,12 +152,12 @@ static void MaybeBuildIdToBuffer(const AddressInfo &info, bool PrefixSpace,
                                  InternalScopedString *buffer) {
   if (info.uuid_size) {
     if (PrefixSpace)
-      buffer->AppendF(" ");
-    buffer->AppendF("(BuildId: ");
+      buffer->Append(" ");
+    buffer->Append("(BuildId: ");
     for (uptr i = 0; i < info.uuid_size; ++i) {
       buffer->AppendF("%02x", info.uuid[i]);
     }
-    buffer->AppendF(")");
+    buffer->Append(")");
   }
 }
 
@@ -249,7 +249,7 @@ void FormattedStackTracePrinter::RenderFrame(InternalScopedString *buffer,
         MaybeBuildIdToBuffer(*info, /*PrefixSpace=*/true, buffer);
 #endif
       } else {
-        buffer->AppendF("(<unknown module>)");
+        buffer->Append("(<unknown module>)");
       }
       break;
     case 'M':
@@ -339,7 +339,7 @@ void StackTracePrinter::RenderSourceLocation(InternalScopedString *buffer,
     buffer->AppendF("%s(%d", StripPathPrefix(file, strip_path_prefix), line);
     if (column > 0)
       buffer->AppendF(",%d", column);
-    buffer->AppendF(")");
+    buffer->Append(")");
     return;
   }