I find this package FTBFS in focal, because llvm-defaults is updated to 10.

https://launchpad.net/ubuntu/+source/ccls/0.20190823.5-1build1

The new version in Debian(sid) can fix this.

How does the SRU procedure work? Is this upstream microrelease suite for SRU?

The diff looks quite minimal.

```
diff -Nru ccls-0.20190823.5/debian/changelog ccls-0.20190823.6/debian/changelog
--- ccls-0.20190823.5/debian/changelog  2019-11-13 00:25:32.000000000 +0800
+++ ccls-0.20190823.6/debian/changelog  2020-04-22 15:03:08.000000000 +0800
@@ -1,3 +1,11 @@
+ccls (0.20190823.6-1) unstable; urgency=medium
+
+  * New upstream release 0.20190823.6
+  * Update Standards-Version to 4.5.0 (no changes)
+  * Run ccls index in autopkgtest
+
+ -- Shengjing Zhu <email address hidden>  Wed, 22 Apr 2020 15:03:08 +0800
+
 ccls (0.20190823.5-1) unstable; urgency=medium
 
   * New upstream release 0.20190823.5
diff -Nru ccls-0.20190823.5/debian/control ccls-0.20190823.6/debian/control
--- ccls-0.20190823.5/debian/control    2019-11-13 00:25:32.000000000 +0800
+++ ccls-0.20190823.6/debian/control    2020-04-22 15:03:08.000000000 +0800
@@ -11,7 +11,7 @@
  llvm-dev,
  python3 <!nocheck>,
  rapidjson-dev,
-Standards-Version: 4.4.1
+Standards-Version: 4.5.0
 Homepage: https://github.com/MaskRay/ccls
 Vcs-Browser: https://salsa.debian.org/zhsj/ccls
 Vcs-Git: https://salsa.debian.org/zhsj/ccls.git
diff -Nru ccls-0.20190823.5/debian/tests/lsp-test ccls-0.20190823.6/debian/tests/lsp-test
--- ccls-0.20190823.5/debian/tests/lsp-test     2019-11-13 00:25:32.000000000 +0800
+++ ccls-0.20190823.6/debian/tests/lsp-test     2020-04-22 15:03:08.000000000 +0800
@@ -7,7 +7,7 @@
 import subprocess
 import time
 
-
+ccls = os.getenv("CCLS", "ccls")
 path = os.path.dirname(os.path.realpath(__file__))
 
 tests = [
@@ -118,17 +118,17 @@
     return json.loads(f.read(size).decode())
 
 
+subprocess.run([ccls, "-index=."], stderr=subprocess.STDOUT).check_returncode()
+
 with subprocess.Popen(
-    [os.getenv("CCLS", "ccls"), "-v=-1"], stdin=subprocess.PIPE, stdout=subprocess.PIPE
+    [ccls, "-v=-1"], stdin=subprocess.PIPE, stdout=subprocess.PIPE
 ) as proc:
     for tt in tests:
         method = tt[0]["method"]
         print("Testing", method)
         proc.stdin.write(encode(tt[0]))
         proc.stdin.flush()
-        if method == "initialize":
-            # wait for ccls to finish indexing
-            time.sleep(2)
+        time.sleep(1)
         got = read(proc.stdout)
         if not tt[1] == got:
             print("Expect:")
diff -Nru ccls-0.20190823.5/src/clang_tu.cc ccls-0.20190823.6/src/clang_tu.cc
--- ccls-0.20190823.5/src/clang_tu.cc   2019-11-13 00:22:48.000000000 +0800
+++ ccls-0.20190823.6/src/clang_tu.cc   2020-04-22 15:02:27.000000000 +0800
@@ -8,6 +8,7 @@
 
 #include <clang/AST/Type.h>
 #include <clang/Lex/Lexer.h>
+#include <llvm/Support/Host.h>
 #include <llvm/Support/Path.h>
 
 using namespace clang;
diff -Nru ccls-0.20190823.5/src/filesystem.cc ccls-0.20190823.6/src/filesystem.cc
--- ccls-0.20190823.5/src/filesystem.cc 2019-11-13 00:22:48.000000000 +0800
+++ ccls-0.20190823.6/src/filesystem.cc 2020-04-22 15:02:27.000000000 +0800
@@ -31,7 +31,8 @@
       curr.pop_back();
       for (sys::fs::directory_iterator i(folder1, ec, false), e; i != e && !ec;
            i.increment(ec)) {
-        std::string path = i->path(), filename = sys::path::filename(path);
+        std::string path = i->path();
+        std::string filename(sys::path::filename(path));
         if ((filename[0] == '.' && filename != ".ccls") ||
             sys::fs::status(path, status, false))
           continue;
diff -Nru ccls-0.20190823.5/src/indexer.cc ccls-0.20190823.6/src/indexer.cc
--- ccls-0.20190823.5/src/indexer.cc    2019-11-13 00:22:48.000000000 +0800
+++ ccls-0.20190823.6/src/indexer.cc    2020-04-22 15:02:27.000000000 +0800
@@ -10,6 +10,7 @@
 #include "sema_manager.hh"
 
 #include <clang/AST/AST.h>
+#include <clang/Basic/TargetInfo.h>
 #include <clang/Frontend/FrontendAction.h>
 #include <clang/Frontend/MultiplexConsumer.h>
 #include <clang/Index/IndexDataConsumer.h>
@@ -508,7 +509,7 @@
     llvm::raw_svector_ostream os(str);
     d->print(os, getDefaultPolicy());
 
-    std::string name = os.str();
+    std::string name(str.data(), str.size());
     simplifyAnonymous(name);
     // Remove \n in DeclPrinter.cpp "{\n" + if(!TerseOutput)something + "}"
     for (std::string::size_type i = 0;;) {
@@ -677,10 +678,13 @@
 public:
   IndexDataConsumer(IndexParam &param) : param(param) {}
   void initialize(ASTContext &ctx) override { this->ctx = param.ctx = &ctx; }
-  bool handleDeclOccurence(const Decl *d, index::SymbolRoleSet roles,
-                           ArrayRef<index::SymbolRelation> relations,
-                           SourceLocation src_loc,
-                           ASTNodeInfo ast_node) override {
+#if LLVM_VERSION_MAJOR < 10 // llvmorg-10-init-12036-g3b9715cb219
+# define handleDeclOccurrence handleDeclOccurence
+#endif
+  bool handleDeclOccurrence(const Decl *d, index::SymbolRoleSet roles,
+                            ArrayRef<index::SymbolRelation> relations,
+                            SourceLocation src_loc,
+                            ASTNodeInfo ast_node) override {
     if (!param.no_linkage) {
       if (auto *nd = dyn_cast<NamedDecl>(d); nd && nd->hasLinkage())
         ;
diff -Nru ccls-0.20190823.5/src/main.cc ccls-0.20190823.6/src/main.cc
--- ccls-0.20190823.5/src/main.cc       2019-11-13 00:22:48.000000000 +0800
+++ ccls-0.20190823.6/src/main.cc       2020-04-22 15:02:27.000000000 +0800
@@ -140,7 +140,7 @@
     if (opt_index.size()) {
       SmallString<256> root(opt_index);
       sys::fs::make_absolute(root);
-      pipeline::standalone(root.str());
+      pipeline::standalone(std::string(root.data(), root.size()));
     } else {
       // The thread that reads from stdin and dispatchs commands to the main
       // thread.
diff -Nru ccls-0.20190823.5/src/pipeline.cc ccls-0.20190823.6/src/pipeline.cc
--- ccls-0.20190823.5/src/pipeline.cc   2019-11-13 00:22:48.000000000 +0800
+++ ccls-0.20190823.6/src/pipeline.cc   2020-04-22 15:02:27.000000000 +0800
@@ -113,7 +113,7 @@
   }
 
   // For inferred files, allow -o a a.cc -> -o b b.cc
-  std::string stem = sys::path::stem(path);
+  StringRef stem = sys::path::stem(path);
   int changed = -1, size = std::min(prev->args.size(), args.size());
   for (int i = 0; i < size; i++)
     if (strcmp(prev->args[i], args[i]) && sys::path::stem(args[i]) != stem) {
diff -Nru ccls-0.20190823.5/src/platform.hh ccls-0.20190823.6/src/platform.hh
--- ccls-0.20190823.5/src/platform.hh   2019-11-13 00:22:48.000000000 +0800
+++ ccls-0.20190823.6/src/platform.hh   2020-04-22 15:02:27.000000000 +0800
@@ -1,14 +1,14 @@
-// Copyright 2017-2018 ccls Authors
+// Copyright 2017-2020 ccls Authors
 // SPDX-License-Identifier: Apache-2.0
 
 #pragma once
 
+#include <llvm/ADT/StringRef.h>
+
 #include <string>
-#include <string_view>
-#include <vector>
 
 namespace ccls {
-std::string normalizePath(const std::string &path);
+std::string normalizePath(llvm::StringRef path);
 
 // Free any unused memory and return it to the system.
 void freeUnusedMemory();
diff -Nru ccls-0.20190823.5/src/platform_posix.cc ccls-0.20190823.6/src/platform_posix.cc
--- ccls-0.20190823.5/src/platform_posix.cc     2019-11-13 00:22:48.000000000 +0800
+++ ccls-0.20190823.6/src/platform_posix.cc     2020-04-22 15:02:27.000000000 +0800
@@ -40,7 +40,7 @@
 void threadEnter();
 }
 
-std::string normalizePath(const std::string &path) {
+std::string normalizePath(llvm::StringRef path) {
   llvm::SmallString<256> p(path);
   llvm::sys::path::remove_dots(p, true);
   return {p.data(), p.size()};
diff -Nru ccls-0.20190823.5/src/platform_win.cc ccls-0.20190823.6/src/platform_win.cc
--- ccls-0.20190823.5/src/platform_win.cc       2019-11-13 00:22:48.000000000 +0800
+++ ccls-0.20190823.6/src/platform_win.cc       2020-04-22 15:02:27.000000000 +0800
@@ -19,17 +19,12 @@
 #include <thread>
 
 namespace ccls {
-std::string normalizePath(const std::string &path) {
-  DWORD retval = 0;
+std::string normalizePath(llvm::StringRef path) {
   TCHAR buffer[MAX_PATH] = TEXT("");
   TCHAR **lpp_part = {NULL};
 
-  std::string result;
-  retval = GetFullPathName(path.c_str(), MAX_PATH, buffer, lpp_part);
-  // fail, return original
-  if (retval == 0)
-    result = path;
-  else
+  std::string result(path);
+  if (GetFullPathName(result.c_str(), MAX_PATH, buffer, lpp_part) != 0)
     result = buffer;
 
   std::replace(result.begin(), result.end(), '\\', '/');
diff -Nru ccls-0.20190823.5/src/project.cc ccls-0.20190823.6/src/project.cc
--- ccls-0.20190823.5/src/project.cc    2019-11-13 00:22:48.000000000 +0800
+++ ccls-0.20190823.6/src/project.cc    2020-04-22 15:02:27.000000000 +0800
@@ -222,7 +222,7 @@
     return {};
   std::vector<const char *> args;
   for (line_iterator i(*mbOrErr.get(), true, '#'), e; i != e; ++i) {
-    std::string line = *i;
+    std::string line(*i);
     doPathMapping(line);
     args.push_back(intern(line));
   }
@@ -632,7 +632,7 @@
 void Project::indexRelated(const std::string &path) {
   auto &gi = g_config->index;
   GroupMatch match(gi.whitelist, gi.blacklist);
-  std::string stem = sys::path::stem(path);
+  StringRef stem = sys::path::stem(path);
   std::vector<const char *> args, extra_args;
   for (const std::string &arg : g_config->clang.extraArgs)
     extra_args.push_back(intern(arg));
diff -Nru ccls-0.20190823.5/src/sema_manager.cc ccls-0.20190823.6/src/sema_manager.cc
--- ccls-0.20190823.5/src/sema_manager.cc       2019-11-13 00:22:48.000000000 +0800
+++ ccls-0.20190823.6/src/sema_manager.cc       2020-04-22 15:02:27.000000000 +0800
@@ -9,6 +9,7 @@
 #include "pipeline.hh"
 #include "platform.hh"
 
+#include <clang/Basic/TargetInfo.h>
 #include <clang/Lex/PreprocessorOptions.h>
 #include <clang/Sema/CodeCompleteConsumer.h>
 #include <clang/Sema/Sema.h>
@@ -622,9 +623,10 @@
         for (const Note &n : d.notes) {
           SmallString<256> str(n.file);
           llvm::sys::path::remove_dots(str, true);
-          Location loc{DocumentUri::fromPath(str.str()),
-                       lsRange{{n.range.start.line, n.range.start.column},
-                               {n.range.end.line, n.range.end.column}}};
+          Location loc{
+              DocumentUri::fromPath(std::string(str.data(), str.size())),
+              lsRange{{n.range.start.line, n.range.start.column},
+                      {n.range.end.line, n.range.end.column}}};
           ls_diag.relatedInformation.push_back({loc, n.message});
         }
       } else {
diff -Nru ccls-0.20190823.5/src/serializer.cc ccls-0.20190823.6/src/serializer.cc
--- ccls-0.20190823.5/src/serializer.cc 2019-11-13 00:22:48.000000000 +0800
+++ ccls-0.20190823.6/src/serializer.cc 2020-04-22 15:02:27.000000000 +0800
@@ -1,4 +1,4 @@
-// Copyright 2017-2018 ccls Authors
+// Copyright 2017-2020 ccls Authors
 // SPDX-License-Identifier: Apache-2.0
 
 #include "serializer.hh"
@@ -13,6 +13,7 @@
 
 #include <llvm/ADT/CachedHashString.h>
 #include <llvm/ADT/DenseSet.h>
+#include <llvm/Support/Allocator.h>
 
 #include <mutex>
 #include <stdexcept>
@@ -216,7 +217,7 @@
   reflectMemberStart(vis);
   REFLECT_MEMBER(line);
   if (gTestOutputMode) {
-    std::string basename = llvm::sys::path::filename(v.resolved_path);
+    std::string basename(llvm::sys::path::filename(v.resolved_path));
     if (v.resolved_path[0] != '&')
       basename = "&" + basename;
     REFLECT_MEMBER2("resolved_path", basename);
```