ClangPchManager: Protect fetchPchSources

It was not protected by a transaction so it was not thread save.

Change-Id: Ib4529d0e94942d3cbafb46705a0256812908c8c6
Reviewed-by: Tim Jenssen <tim.jenssen@qt.io>

1 files changed, 12 insertions, 1 deletions

diff --git a/src/tools/clangpchmanagerbackend/source/builddependenciesstorage.h b/src/tools/clangpchmanagerbackend/source/builddependenciesstorage.h
index 00bb429dba..f75d83b572 100644
--- a/src/tools/clangpchmanagerbackend/source/builddependenciesstorage.h
+++ b/src/tools/clangpchmanagerbackend/source/builddependenciesstorage.h
@@ -68,7 +68,18 @@ public:
 
     FilePathIds fetchPchSources(ProjectPartId projectPartId) const override
     {
-        return fetchPchSourcesStatement.template values<FilePathId>(1024, projectPartId.projectPathId);
+        try {
+            Sqlite::DeferredTransaction transaction{database};
+
+            FilePathIds values = fetchPchSourcesStatement
+                                     .template values<FilePathId>(1024, projectPartId.projectPathId);
+
+            transaction.commit();
+
+            return values;
+        } catch (const Sqlite::StatementIsBusy &) {
+            return fetchPchSources(projectPartId);
+        }
     }
 
     FilePathIds fetchSources(ProjectPartId projectPartId) const override