test: Add a min-llvm-version directive

We've got tests which require a particular version of LLVM to run as they're
testing bug fixes. Our build system, however, supports multiple LLVM versions,
so we can't run these tests on all LLVM versions.

This adds a new `min-llvm-version` directive for tests so they can opt out of
being run on older versions of LLVM. This then namely applies that logic to the
`issue-36023.rs` test case and...

Closes #36138

Author: alexcrichton

mk/main.mk

@@ -348,6 +348,7 @@ LLVM_AS_$(1)=$$(CFG_LLVM_INST_DIR_$(1))/bin/llvm-as$$(X_$(1))
 LLC_$(1)=$$(CFG_LLVM_INST_DIR_$(1))/bin/llc$$(X_$(1))
 
 LLVM_ALL_COMPONENTS_$(1)=$$(shell "$$(LLVM_CONFIG_$(1))" --components)
+LLVM_VERSION_$(1)=$$(shell "$$(LLVM_CONFIG_$(1))" --version)
 
 endef
 

mk/tests.mk

@@ -649,6 +649,7 @@ CTEST_COMMON_ARGS$(1)-T-$(2)-H-$(3) = \
 	--lldb-python $$(CFG_LLDB_PYTHON) \
         --gdb-version="$(CFG_GDB_VERSION)" \
         --lldb-version="$(CFG_LLDB_VERSION)" \
+        --llvm-version="$$(LLVM_VERSION_$(3))" \
         --android-cross-path=$(CFG_ARM_LINUX_ANDROIDEABI_NDK) \
         --adb-path=$(CFG_ADB) \
         --adb-test-dir=$(CFG_ADB_TEST_DIR) \

src/bootstrap/check.rs

@@ -148,6 +148,9 @@ pub fn compiletest(build: &Build,
     if let Some(ref dir) = build.lldb_python_dir {
         cmd.arg("--lldb-python-dir").arg(dir);
     }
+    let llvm_config = build.llvm_config(target);
+    let llvm_version = output(Command::new(&llvm_config).arg("--version"));
+    cmd.arg("--llvm-version").arg(llvm_version);
 
     cmd.args(&build.flags.args);
 
@@ -158,7 +161,6 @@ pub fn compiletest(build: &Build,
     // Only pass correct values for these flags for the `run-make` suite as it
     // requires that a C++ compiler was configured which isn't always the case.
     if suite == "run-make" {
-        let llvm_config = build.llvm_config(target);
         let llvm_components = output(Command::new(&llvm_config).arg("--components"));
         let llvm_cxxflags = output(Command::new(&llvm_config).arg("--cxxflags"));
         cmd.arg("--cc").arg(build.cc(target))

src/test/run-pass/issue-36023.rs

@@ -8,6 +8,8 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+// min-llvm-version 3.9
+
 use std::ops::Deref;
 
 fn main() {

src/tools/compiletest/src/common.rs

@@ -152,6 +152,9 @@ pub struct Config {
     // Version of LLDB
     pub lldb_version: Option<String>,
 
+    // Version of LLVM
+    pub llvm_version: Option<String>,
+
     // Path to the android tools
     pub android_cross_path: PathBuf,
 

src/tools/compiletest/src/header.rs

@@ -44,7 +44,9 @@ impl EarlyProps {
                 (config.mode == common::Pretty && parse_name_directive(ln, "ignore-pretty")) ||
                 (config.target != config.host &&
                  parse_name_directive(ln, "ignore-cross-compile")) ||
-                ignore_gdb(config, ln) || ignore_lldb(config, ln);
+                ignore_gdb(config, ln) ||
+                ignore_lldb(config, ln) ||
+                ignore_llvm(config, ln);
 
             props.should_fail = props.should_fail || parse_name_directive(ln, "should-fail");
         });
@@ -115,6 +117,24 @@ impl EarlyProps {
                 false
             }
         }
+
+        fn ignore_llvm(config: &Config, line: &str) -> bool {
+            if let Some(ref actual_version) = config.llvm_version {
+                if line.contains("min-llvm-version") {
+                    let min_version = line.trim()
+                        .split(' ')
+                        .last()
+                        .expect("Malformed llvm version directive");
+                    // Ignore if actual version is smaller the minimum required
+                    // version
+                    &actual_version[..] < min_version
+                } else {
+                    false
+                }
+            } else {
+                false
+            }
+        }
     }
 }
 

src/tools/compiletest/src/main.rs

@@ -99,6 +99,7 @@ pub fn parse_config(args: Vec<String> ) -> Config {
           optopt("", "host", "the host to build for", "HOST"),
           optopt("", "gdb-version", "the version of GDB used", "VERSION STRING"),
           optopt("", "lldb-version", "the version of LLDB used", "VERSION STRING"),
+          optopt("", "llvm-version", "the version of LLVM used", "VERSION STRING"),
           optopt("", "android-cross-path", "Android NDK standalone path", "PATH"),
           optopt("", "adb-path", "path to the android debugger", "PATH"),
           optopt("", "adb-test-dir", "path to tests for the android debugger", "PATH"),
@@ -170,6 +171,7 @@ pub fn parse_config(args: Vec<String> ) -> Config {
         host: opt_str2(matches.opt_str("host")),
         gdb_version: extract_gdb_version(matches.opt_str("gdb-version")),
         lldb_version: extract_lldb_version(matches.opt_str("lldb-version")),
+        llvm_version: matches.opt_str("llvm-version"),
         android_cross_path: opt_path(matches, "android-cross-path"),
         adb_path: opt_str2(matches.opt_str("adb-path")),
         adb_test_dir: format!("{}/{}",