[clang][driver] Enable MisExpect diagnostics flag outside of CC1

[paulkirth]

Summary

Previously we only accepted the -fdiagnostics-misexpect-tolerance= at
CC1, when it should have been handled identically to
-fdiagnostics-hotness-threshold=. It should not have been required to
pass this flag w/ -Xclang as reported here:
https://reviews.llvm.org/D115907#inline-1440745

[phosek]

LGTM

[hans]

clang/test/Profile/misexpect-branch.c

10 ↗

(On Diff #516922)

The more common way to test this would be a test under clang/test/Driver/ that just checks that forwarding the flag works.

[paulkirth]

clang/test/Profile/misexpect-branch.c

10 ↗

(On Diff #516922)

Good point, I just defaulted to adding the RUN line here, but that's definitely the right way to test this.

[paulkirth]

Migrate to a Driver test

[hans]

clang/test/Driver/clang_f_opts.c

144

Instead of checking for absence of the warning, could we just check that the flag is present among the cc1 flags? I think that's how most of the other tests here do it.

[paulkirth]

Update test to check if the flag is in cc1, instead of just looking for a warning.

clang/test/Driver/clang_f_opts.c

144

It took me a minute to realize what you meant here. I was pretty surprised to find out that "-fdiagnostics-misexpect-tolerance=10" is how we test for cc1, but '-fdiagnostics-misexpect-tolerance=' is a test for an error/warning string. The reason I wrote the check this way was so that I wouldn't accidentally match on the non-warning case.

TBH Ithink checking the cc1 flags like this is pretty brittle. They would all silently pass (even when they shouldn't) if the warning diagnostic used " instead of '. I'm sure some other tests would fail/need to be changed in that case, but there wouldn't be any indication that these tests wouldn't be functioning as intended.

[hans]

lgtm

clang/lib/Driver/ToolChains/Clang.cpp

static void RenderDiagnosticsOptions(const Driver &D, const ArgList &Args,
 
   if (const Arg *A =
           Args.getLastArg(options::OPT_fdiagnostics_hotness_threshold_EQ)) {
     std::string Opt =
         std::string("-fdiagnostics-hotness-threshold=") + A->getValue();
     CmdArgs.push_back(Args.MakeArgString(Opt));
   }
 
+  if (const Arg *A =
+          Args.getLastArg(options::OPT_fdiagnostics_misexpect_tolerance_EQ)) {
+    std::string Opt =
+        std::string("-fdiagnostics-misexpect-tolerance=") + A->getValue();
+    CmdArgs.push_back(Args.MakeArgString(Opt));
+  }
+
   if (const Arg *A = Args.getLastArg(options::OPT_fdiagnostics_format_EQ)) {
     CmdArgs.push_back("-fdiagnostics-format");
     CmdArgs.push_back(A->getValue());
     if (StringRef(A->getValue()) == "sarif" ||
         StringRef(A->getValue()) == "SARIF")
       D.Diag(diag::warn_drv_sarif_format_unstable);
   }
 

clang/test/Driver/clang_f_opts.c

 // RUN: %clang -### -S -fprofile-instr-use %s 2>&1 | FileCheck -check-prefix=CHECK-PROFILE-USE %s
 // RUN: mkdir -p %t.d/some/dir
 // RUN: %clang -### -S -fprofile-use=%t.d/some/dir %s 2>&1 | FileCheck -check-prefix=CHECK-PROFILE-USE-DIR %s
 // RUN: %clang -### -S -fprofile-instr-use=/tmp/somefile.prof %s 2>&1 | FileCheck -check-prefix=CHECK-PROFILE-USE-FILE %s
 // CHECK-PROFILE-USE: "-fprofile-instrument-use-path=default.profdata"
 // CHECK-PROFILE-USE-DIR: "-fprofile-instrument-use-path={{.*}}.d/some/dir{{/|\\\\}}default.profdata"
 // CHECK-PROFILE-USE-FILE: "-fprofile-instrument-use-path=/tmp/somefile.prof"
 
+// RUN: %clang -### -S -fprofile-instr-use=%t.profdata -fdiagnostics-misexpect-tolerance=10 -Wmisexpect %s 2>&1 | FileCheck %s --check-prefix=CHECK-MISEXPECT-TOLLERANCE
+// CHECK-MISEXPECT-TOLLERANCE-NOT: argument unused {{.*}}-fdiagnostics-misexpect-tolerance=
+
 // RUN: %clang -### -S -fvectorize %s 2>&1 | FileCheck -check-prefix=CHECK-VECTORIZE %s
 // RUN: %clang -### -S -fno-vectorize -fvectorize %s 2>&1 | FileCheck -check-prefix=CHECK-VECTORIZE %s
 // RUN: %clang -### -S -fno-vectorize %s 2>&1 | FileCheck -check-prefix=CHECK-NO-VECTORIZE %s
 // RUN: %clang -### -S -fvectorize -fno-vectorize %s 2>&1 | FileCheck -check-prefix=CHECK-NO-VECTORIZE %s
 // RUN: %clang -### -S -ftree-vectorize %s 2>&1 | FileCheck -check-prefix=CHECK-VECTORIZE %s
 // RUN: %clang -### -S -fno-tree-vectorize -fvectorize %s 2>&1 | FileCheck -check-prefix=CHECK-VECTORIZE %s
 // RUN: %clang -### -S -fno-tree-vectorize %s 2>&1 | FileCheck -check-prefix=CHECK-NO-VECTORIZE %s
 // RUN: %clang -### -S -ftree-vectorize -fno-vectorize %s 2>&1 | FileCheck -check-prefix=CHECK-NO-VECTORIZE %s