Auto merge of rust-lang#81688 - pnkfelix:fix-llvm-version-check-in-ru…

…n-make-tests, r=simulacrum

Use `# min-llvm-version: 11.0` to force a minimum LLVM version

Use `# min-llvm-version: 11.0` to force a minimum LLVM version, rather than ad-hoc internal solution.

In particular: the specific code to define LLVM_VERSION_11_PLUS here was, for some reason, using `$(shell ...)` with bash-specific variable replacement code. On non-bash platforms like dash, that `shell` invocation would fail, and the
LLVM_VERSION_11_PLUS check would always fail, the test would always be ignored, and thus be treated as a "success" (in the sense that `--bless` would never do anything).

 * Note in particular that GNU Make treats the SHELL variable as a very special case: it does not inherit the value of SHELL from the user's environment. Except on Windows. See more explanation in the [GNU Make docs](https://www.gnu.org/software/make/manual/html_node/Choosing-the-Shell.html).
 * The effect of this is that these tests end up using `/bin/sh` (except on Windows) for their `$(shell ...)` invocations, and thus we see differing behaviors depending on whether your `/bin/sh` links to `/bin/dash` or to `/bin/bash`.

This was causing me a lot of pain.

src/test/run-make-fulldeps/coverage-llvmir/Makefile

@@ -1,4 +1,5 @@
 # needs-profiler-support
+# min-llvm-version: 11.0
 
 -include ../coverage/coverage_tools.mk
 
@@ -48,12 +49,7 @@ else
 		-DINSTR_PROF_ORDERFILE='$(DATA_SECTION_PREFIX)__llvm_orderfile'
 endif
 
-ifeq ($(LLVM_VERSION_11_PLUS),true)
 all: test_llvm_ir
-else
-$(info Rust option `-Z instrument-coverage` requires LLVM 11 or higher. Test skipped.)
-all:
-endif
 
 test_llvm_ir:
 	# Compile the test program with non-experimental coverage instrumentation, and generate LLVM IR

src/test/run-make-fulldeps/coverage-reports/Makefile

@@ -1,5 +1,7 @@
+# ignore-test Broken; accidentally silently ignored on Linux CI; FIXME(#81688)
 # needs-profiler-support
 # ignore-windows-gnu
+# min-llvm-version: 11.0
 
 # FIXME(mati865): MinGW GCC miscompiles compiler-rt profiling library but with Clang it works
 # properly. Since we only have GCC on the CI ignore the test for now.
@@ -67,12 +69,7 @@ ifdef RUSTC_BLESS_TEST
 DEBUG_FLAG=--debug
 endif
 
-ifeq ($(LLVM_VERSION_11_PLUS),true)
 all: $(patsubst $(SOURCEDIR)/lib/%.rs,%,$(wildcard $(SOURCEDIR)/lib/*.rs)) $(patsubst $(SOURCEDIR)/%.rs,%,$(wildcard $(SOURCEDIR)/*.rs))
-else
-$(info Rust option `-Z instrument-coverage` requires LLVM 11 or higher. Test skipped.)
-all:
-endif
 
 # Ensure there are no `expected` results for tests that may have been removed or renamed
 .PHONY: clear_expected_if_blessed

src/test/run-make-fulldeps/coverage-spanview/Makefile

@@ -1,4 +1,5 @@
 # needs-profiler-support
+# min-llvm-version: 11.0
 
 -include ../coverage/coverage_tools.mk
 
@@ -20,12 +21,7 @@ For revisions in Pull Requests (PR):
 endef
 export SPANVIEW_HEADER
 
-ifeq ($(LLVM_VERSION_11_PLUS),true)
 all: $(patsubst $(SOURCEDIR)/lib/%.rs,%,$(wildcard $(SOURCEDIR)/lib/*.rs)) $(patsubst $(SOURCEDIR)/%.rs,%,$(wildcard $(SOURCEDIR)/*.rs))
-else
-$(info Rust option `-Z instrument-coverage` requires LLVM 11 or higher. Test skipped.)
-all:
-endif
 
 # Ensure there are no `expected` results for tests that may have been removed or renamed
 .PHONY: clear_expected_if_blessed

src/test/run-make-fulldeps/coverage/coverage_tools.mk

@@ -14,10 +14,3 @@
 # Therefore, `-C link-dead-code` is no longer automatically enabled.
 
 UNAME = $(shell uname)
-
-# Rust option `-Z instrument-coverage` uses LLVM Coverage Mapping Format version 4,
-# which requires LLVM 11 or greater.
-LLVM_VERSION_11_PLUS := $(shell \
-		LLVM_VERSION=$$("$(LLVM_BIN_DIR)"/llvm-config --version) && \
-		LLVM_VERSION_MAJOR=$${LLVM_VERSION/.*/} && \
-		[ $$LLVM_VERSION_MAJOR -ge 11 ] && echo true || echo false)