Add -fbuild-session-file as an alternative to -fbuild-session-timestamp
Build systems tend to traffic in files and modification times, so having
them touch a file at the beginning of the build can be easier than
having them update the compile command they use every time they build.
llvm-svn: 214577
diff --git a/clang/lib/Driver/Tools.cpp b/clang/lib/Driver/Tools.cpp
index b607f2f..bcc8056 100644
--- a/clang/lib/Driver/Tools.cpp
+++ b/clang/lib/Driver/Tools.cpp
@@ -3855,8 +3855,22 @@
Args.AddLastArg(CmdArgs, options::OPT_fbuild_session_timestamp);
+ if (Arg *A = Args.getLastArg(options::OPT_fbuild_session_file)) {
+ if (Args.hasArg(options::OPT_fbuild_session_timestamp))
+ D.Diag(diag::err_drv_argument_not_allowed_with)
+ << A->getAsString(Args) << "-fbuild-session-timestamp";
+
+ llvm::sys::fs::file_status Status;
+ if (llvm::sys::fs::status(A->getValue(), Status))
+ D.Diag(diag::err_drv_no_such_file) << A->getValue();
+ auto Timestamp = Status.getLastModificationTime().toEpochTime();
+ CmdArgs.push_back(Args.MakeArgString("-fbuild-session-timestamp=" +
+ std::to_string(Timestamp)));
+ }
+
if (Args.getLastArg(options::OPT_fmodules_validate_once_per_build_session)) {
- if (!Args.getLastArg(options::OPT_fbuild_session_timestamp))
+ if (!Args.getLastArg(options::OPT_fbuild_session_timestamp,
+ options::OPT_fbuild_session_file))
D.Diag(diag::err_drv_modules_validate_once_requires_timestamp);
Args.AddLastArg(CmdArgs,