[Driver] Add compiler option to generate a reproducer

One way to currently test the reproducers is to setup
"FORCE_CLANG_DIAGNOSTICS_CRASH=1" before invoking clang. This simulates
a crash and produces the same contents needed by the reproducers.  The
reproducers are specially useful when triaging Modules issues, not only
on crashes, but also for reproducing misleading warnings, errors, etc.

Add a '-gen-reproducer' driver option to clang (or any similar name) and
give users a flag option.

Note that clang already has a -fno-crash-diagnostics, which disables the
crash reproducers. I've decided not to propose "-fcrash-diagnostics"
since it doesn't convey the ideia of reproduction despite a crash.

rdar://problem/24114619

Differential Revision: https://reviews.llvm.org/D27604

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@300109 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/docs/UsersManual.rst b/docs/UsersManual.rst
index beb55ca251e7cbfc67cd7564d000d37678083720..7362456202ba1b559ce8a00be3fb4374bed9bca0 100644 (file)
--- a/docs/UsersManual.rst
+++ b/docs/UsersManual.rst
@@ -562,6 +562,16 @@ control the crash diagnostics.
 The -fno-crash-diagnostics flag can be helpful for speeding the process
 of generating a delta reduced test case.
 
+Clang is also capable of generating preprocessed source file(s) and associated
+run script(s) even without a crash. This is specially useful when trying to
+generate a reproducer for warnings or errors while using modules.
+
+.. option:: -gen-reproducer
+
+  Generates preprocessed source files, a reproducer script and if relevant, a
+  cache containing: built module pcm's and all headers needed to rebuilt the
+  same modules.
+
 .. _rpass:
 
 Options to Emit Optimization Reports

diff --git a/include/clang/Basic/DiagnosticDriverKinds.td b/include/clang/Basic/DiagnosticDriverKinds.td
index 836b4677409f8c85cf32f4ceac1a12c47d2fd8f1..3980805ef9bcda0b32a664912642df7ea259f2e9 100644 (file)
--- a/include/clang/Basic/DiagnosticDriverKinds.td
+++ b/include/clang/Basic/DiagnosticDriverKinds.td
@@ -94,7 +94,7 @@ def err_drv_compilationdatabase : Error<
 def err_drv_command_signalled : Error<
   "%0 command failed due to signal (use -v to see invocation)">;
 def err_drv_force_crash : Error<
-  "failing because environment variable '%0' is set">;
+  "failing because %select{environment variable 'FORCE_CLANG_DIAGNOSTICS_CRASH' is set|'-gen-reproducer' is used}0">;
 def err_drv_invalid_mfloat_abi : Error<
   "invalid float ABI '%0'">;
 def err_drv_invalid_libcxx_deployment : Error<

diff --git a/include/clang/Driver/Driver.h b/include/clang/Driver/Driver.h
index e653c7ca959f43976e8f9c3ec39a4d44b1025869..1009754a15d52a6987b2081e4760b8956885cb43 100644 (file)
--- a/include/clang/Driver/Driver.h
+++ b/include/clang/Driver/Driver.h
@@ -216,6 +216,11 @@ public:
   /// Use lazy precompiled headers for PCH support.
   unsigned CCCUsePCH : 1;
 
+  /// Force clang to emit reproducer for driver invocation. This is enabled
+  /// indirectly by setting FORCE_CLANG_DIAGNOSTICS_CRASH environment variable
+  /// or when using the -gen-reproducer driver flag.
+  unsigned GenReproducer : 1;
+
 private:
   /// Certain options suppress the 'no input files' warning.
   unsigned SuppressMissingInputWarning : 1;

diff --git a/include/clang/Driver/Options.td b/include/clang/Driver/Options.td
index da1dd361ede222f1047c7e637bcda8c3b965d90a..6c78078ce60ce3ff92ea5fc612d5377e1bca9bbf 100644 (file)
--- a/include/clang/Driver/Options.td
+++ b/include/clang/Driver/Options.td
@@ -265,6 +265,8 @@ def arcmt_migrate_report_output : Separate<["-"], "arcmt-migrate-report-output">
 def arcmt_migrate_emit_arc_errors : Flag<["-"], "arcmt-migrate-emit-errors">,
   HelpText<"Emit ARC errors even if the migrator can fix them">,
   Flags<[CC1Option]>;
+def gen_reproducer: Flag<["-"], "gen-reproducer">, InternalDebugOpt,
+  HelpText<"Auto-generates preprocessed source files and a reproduction script">;
 
 def _migrate : Flag<["--"], "migrate">, Flags<[DriverOption]>,
   HelpText<"Run the migrator">;
@@ -701,7 +703,8 @@ def fconstexpr_depth_EQ : Joined<["-"], "fconstexpr-depth=">, Group<f_Group>;
 def fconstexpr_steps_EQ : Joined<["-"], "fconstexpr-steps=">, Group<f_Group>;
 def fconstexpr_backtrace_limit_EQ : Joined<["-"], "fconstexpr-backtrace-limit=">,
                                     Group<f_Group>;
-def fno_crash_diagnostics : Flag<["-"], "fno-crash-diagnostics">, Group<f_clang_Group>, Flags<[NoArgumentUnused]>;
+def fno_crash_diagnostics : Flag<["-"], "fno-crash-diagnostics">, Group<f_clang_Group>, Flags<[NoArgumentUnused]>,
+  HelpText<"Disable auto-generation of preprocessed source files and a script for reproduction during a clang crash">;
 def fcreate_profile : Flag<["-"], "fcreate-profile">, Group<f_Group>;
 def fcxx_exceptions: Flag<["-"], "fcxx-exceptions">, Group<f_Group>,
   HelpText<"Enable C++ exceptions">, Flags<[CC1Option]>;

diff --git a/lib/Driver/Driver.cpp b/lib/Driver/Driver.cpp
index dda754127766e908855d9a31da472686276c4b8f..f36deff5d734202c3ec94c9cd38b8fbbd128be71 100644 (file)
--- a/lib/Driver/Driver.cpp
+++ b/lib/Driver/Driver.cpp
@@ -91,7 +91,7 @@ Driver::Driver(StringRef ClangExecutable, StringRef DefaultTargetTriple,
       CCCPrintBindings(false), CCPrintHeaders(false), CCLogDiagnostics(false),
       CCGenDiagnostics(false), DefaultTargetTriple(DefaultTargetTriple),
       CCCGenericGCCName(""), CheckInputsExist(true), CCCUsePCH(true),
-      SuppressMissingInputWarning(false) {
+      GenReproducer(false), SuppressMissingInputWarning(false) {
 
   // Provide a sane fallback if no VFS is specified.
   if (!this->VFS)
@@ -620,6 +620,9 @@ Compilation *Driver::BuildCompilation(ArrayRef<const char *> ArgList) {
     CCCGenericGCCName = A->getValue();
   CCCUsePCH =
       Args.hasFlag(options::OPT_ccc_pch_is_pch, options::OPT_ccc_pch_is_pth);
+  GenReproducer = Args.hasFlag(options::OPT_gen_reproducer,
+                               options::OPT_fno_crash_diagnostics,
+                               !!::getenv("FORCE_CLANG_DIAGNOSTICS_CRASH"));
   // FIXME: DefaultTargetTriple is used by the target-prefixed calls to as/ld
   // and getToolChain is const.
   if (IsCLMode()) {

diff --git a/test/Driver/crash-report-crashfile.m b/test/Driver/crash-report-crashfile.m
index 71f6e7a9e1294ebf3c69b2b418d497147afce821..fbfb532703efeb5eebedf7ef8db30976b691c800 100644 (file)
--- a/test/Driver/crash-report-crashfile.m
+++ b/test/Driver/crash-report-crashfile.m
@@ -3,15 +3,32 @@
 // RUN: mkdir -p %t/i %t/m %t
 
 // RUN: not env FORCE_CLANG_DIAGNOSTICS_CRASH= TMPDIR=%t TEMP=%t TMP=%t \
-// RUN: %clang -fsyntax-only %s -I %S/Inputs/module -isysroot %/t/i/    \
-// RUN: -fmodules -fmodules-cache-path=%t/m/ -DFOO=BAR 2>&1 | FileCheck %s
+// RUN: %clang -fsyntax-only %s \
+// RUN:   -I %S/Inputs/module -isysroot %/t/i/ \
+// RUN:   -fmodules -fmodules-cache-path=%t/m/ -DFOO=BAR 2>&1 | \
+// RUN:   FileCheck -check-prefix=CRASH_ENV %s
+
+// RUN: not env TMPDIR=%t TEMP=%t TMP=%t \
+// RUN: %clang -gen-reproducer -fsyntax-only %s \
+// RUN:   -I %S/Inputs/module -isysroot %/t/i/ \
+// RUN:   -fmodules -fmodules-cache-path=%t/m/ -DFOO=BAR 2>&1 | \
+// RUN:   FileCheck -check-prefix=CRASH_FLAG %s
 
 @import simple;
 const int x = MODULE_MACRO;
 
-// CHECK: Preprocessed source(s) and associated run script(s) are located at:
-// CHECK-NEXT: note: diagnostic msg: {{.*}}.m
-// CHECK-NEXT: note: diagnostic msg: {{.*}}.cache
-// CHECK-NEXT: note: diagnostic msg: {{.*}}.sh
-// CHECK-NEXT: note: diagnostic msg: Crash backtrace is located in
-// CHECK-NEXT: note: diagnostic msg: {{.*}}Library/Logs/DiagnosticReports{{.*}}
+// CRASH_ENV: failing because environment variable 'FORCE_CLANG_DIAGNOSTICS_CRASH' is set
+// CRASH_ENV: Preprocessed source(s) and associated run script(s) are located at:
+// CRASH_ENV-NEXT: note: diagnostic msg: {{.*}}.m
+// CRASH_ENV-NEXT: note: diagnostic msg: {{.*}}.cache
+// CRASH_ENV-NEXT: note: diagnostic msg: {{.*}}.sh
+// CRASH_ENV-NEXT: note: diagnostic msg: Crash backtrace is located in
+// CRASH_ENV-NEXT: note: diagnostic msg: {{.*}}Library/Logs/DiagnosticReports{{.*}}
+
+// CRASH_FLAG: failing because '-gen-reproducer' is used
+// CRASH_FLAG: Preprocessed source(s) and associated run script(s) are located at:
+// CRASH_FLAG-NEXT: note: diagnostic msg: {{.*}}.m
+// CRASH_FLAG-NEXT: note: diagnostic msg: {{.*}}.cache
+// CRASH_FLAG-NEXT: note: diagnostic msg: {{.*}}.sh
+// CRASH_FLAG-NEXT: note: diagnostic msg: Crash backtrace is located in
+// CRASH_FLAG-NEXT: note: diagnostic msg: {{.*}}Library/Logs/DiagnosticReports{{.*}}

diff --git a/tools/driver/driver.cpp b/tools/driver/driver.cpp
index 61613028625b3557594896391a2c3ef1b93d0e48..626d006ac0d8498eff19da7eaa9e859435ad5214 100644 (file)
--- a/tools/driver/driver.cpp
+++ b/tools/driver/driver.cpp
@@ -460,8 +460,9 @@ int main(int argc_, const char **argv_) {
     Res = TheDriver.ExecuteCompilation(*C, FailingCommands);
 
   // Force a crash to test the diagnostics.
-  if (::getenv("FORCE_CLANG_DIAGNOSTICS_CRASH")) {
-    Diags.Report(diag::err_drv_force_crash) << "FORCE_CLANG_DIAGNOSTICS_CRASH";
+  if (TheDriver.GenReproducer) {
+    Diags.Report(diag::err_drv_force_crash)
+        << !::getenv("FORCE_CLANG_DIAGNOSTICS_CRASH");
 
     // Pretend that every command failed.
     FailingCommands.clear();