Possible fix for ldc-profgen errors

[wilsonk]

Here is a diff that 'fixes' the ldc-profgen errors (by avoiding them) for several versions of linux I have tried. Not really sure if the is the best way to do this, but I think it should work for now at least. Hopefully we can fix the ldc-profgen issue later and this won't be necessary anyways.

This diff uses the LDC_PROFGEN environment variable to avoid building on the default build (ie. the env var is not set at all). Then one can use this env var on the CI/CD to enable the ldc-profgen compilation on the ci server via export LDC_PROFGEN="ENABLE_LDC_PROFGEN=ON" or some such (not totally sure how to set things on the ci server).

diff --git a/Makefile b/Makefile
index 9a28d62067..2650f72a9a 100644
--- a/Makefile
+++ b/Makefile
@@ -100,9 +100,11 @@ html: $(BUILD_EXE)
 phobos:
 	cd phobos && make
 
+BUILD_LDC_PROFGEN := $(if $(LDC_PROFGEN),-D$(LDC_PROFGEN),)
+
 ldc:
 	mkdir -p ldc-build
-	cd ldc-build && cmake ../ldc && make
+	cd ldc-build && cmake ../ldc ${BUILD_LDC_PROFGEN} && make
 
 # Creates Exuberant Ctags tags file
 tags: Makefile $(ECTAGS_FILES)
diff --git a/ldc/tools/CMakeLists.txt b/ldc/tools/CMakeLists.txt
index facb939472..c95b078b9c 100644
--- a/ldc/tools/CMakeLists.txt
+++ b/ldc/tools/CMakeLists.txt
@@ -25,44 +25,52 @@ install(PROGRAMS ${LDCPRUNECACHE_EXE_FULL} DESTINATION ${CMAKE_INSTALL_PREFIX}/b
 
 #############################################################################
 # Build ldc-profdata for converting profile data formats (source version depends on LLVM version)
-set(LDCPROFDATA_SRC ldc-profdata/llvm-profdata-${LLVM_VERSION_MAJOR}.${LLVM_VERSION_MINOR}.cpp)
-if (EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/${LDCPROFDATA_SRC})
-    add_executable(ldc-profdata ${LDCPROFDATA_SRC})
-    set_target_properties(
-        ldc-profdata PROPERTIES
-        RUNTIME_OUTPUT_DIRECTORY ${PROJECT_BINARY_DIR}/bin
-        COMPILE_FLAGS "${LLVM_CXXFLAGS} ${LDC_CXXFLAGS}"
-        LINK_FLAGS "${SANITIZE_LDFLAGS}"
-    )
-    target_link_libraries(ldc-profdata ${LLVM_LIBRARIES} ${CMAKE_DL_LIBS} ${LLVM_LDFLAGS})
-    install(TARGETS ldc-profdata DESTINATION ${CMAKE_INSTALL_PREFIX}/bin)
-else()
-    message(WARNING "ldc-profdata source (${LDCPROFDATA_SRC}) not found")
+# ENABLE_LDC_PROFGEN works for profgen and profdata
+option(ENABLE_LDC_PROFGEN "LDC-profdata feature defaults to off" OFF)  # See below
+if(ENABLE_LDC_PROFGEN)
+    set(LDCPROFDATA_SRC ldc-profdata/llvm-profdata-${LLVM_VERSION_MAJOR}.${LLVM_VERSION_MINOR}.cpp)
+    if (EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/${LDCPROFDATA_SRC})
+        add_executable(ldc-profdata ${LDCPROFDATA_SRC})
+        set_target_properties(
+            ldc-profdata PROPERTIES
+            RUNTIME_OUTPUT_DIRECTORY ${PROJECT_BINARY_DIR}/bin
+            COMPILE_FLAGS "${LLVM_CXXFLAGS} ${LDC_CXXFLAGS}"
+            LINK_FLAGS "${SANITIZE_LDFLAGS}"
+        )
+        target_link_libraries(ldc-profdata ${LLVM_LIBRARIES} ${CMAKE_DL_LIBS} ${LLVM_LDFLAGS})
+        install(TARGETS ldc-profdata DESTINATION ${CMAKE_INSTALL_PREFIX}/bin)
+    else()
+        message(WARNING "ldc-profdata source (${LDCPROFDATA_SRC}) not found")
+    endif()
 endif()
 
+
 #############################################################################
 # Build ldc-profgen utility that generates a profile data file from given perf script
 # data files for sample-based profile guided optimization (-fprofile-sample-use).
 # https://llvm.org/docs/CommandGuide/llvm-profgen.html
 # The source in ldc-profgen/ldc-profgen-xx.x is an unmodified copy of llvm's llvm-profgen source dir.
-if(LDC_LLVM_VER GREATER_EQUAL 1400)
-    macro(add_llvm_tool llvm_name)
-        string(REPLACE "llvm-" "ldc-" ldc_name ${llvm_name})
-        message(STATUS "Configuring ${ldc_name} build target")
-        add_executable(${ldc_name} ${ARGN})
-        set_target_properties(
-            ${ldc_name} PROPERTIES
-            RUNTIME_OUTPUT_DIRECTORY ${PROJECT_BINARY_DIR}/bin
-            COMPILE_FLAGS "${LLVM_CXXFLAGS} ${LDC_CXXFLAGS}"
-            LINK_FLAGS "${SANITIZE_LDFLAGS}"
-        )
-        target_link_libraries(${ldc_name} ${LLVM_LIBRARIES} ${CMAKE_DL_LIBS} ${LLVM_LDFLAGS})
-        install(TARGETS ${ldc_name} DESTINATION ${CMAKE_INSTALL_PREFIX}/bin)
-    endmacro()
-    if (IS_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/ldc-profgen/ldc-profgen-${LLVM_VERSION_MAJOR}.${LLVM_VERSION_MINOR})
-        add_subdirectory(ldc-profgen/ldc-profgen-${LLVM_VERSION_MAJOR}.${LLVM_VERSION_MINOR})
-    else()
-        message(WARNING "ldc-profgen source not found (${CMAKE_CURRENT_SOURCE_DIR}/ldc-profgen/ldc-profgen-${LLVM_VERSION_MAJOR}.${LLVM_VERSION_MINOR})")
+option(ENABLE_LDC_PROFGEN "LDC-profgen feature defaults to off" OFF)  # See below
+if(ENABLE_LDC_PROFGEN)
+    if(LDC_LLVM_VER GREATER_EQUAL 1400)
+        macro(add_llvm_tool llvm_name)
+            string(REPLACE "llvm-" "ldc-" ldc_name ${llvm_name})
+            message(STATUS "Configuring ${ldc_name} build target")
+            add_executable(${ldc_name} ${ARGN})
+            set_target_properties(
+                ${ldc_name} PROPERTIES
+                RUNTIME_OUTPUT_DIRECTORY ${PROJECT_BINARY_DIR}/bin
+                COMPILE_FLAGS "${LLVM_CXXFLAGS} ${LDC_CXXFLAGS}"
+                LINK_FLAGS "${SANITIZE_LDFLAGS}"
+            )
+            target_link_libraries(${ldc_name} ${LLVM_LIBRARIES} ${CMAKE_DL_LIBS} ${LLVM_LDFLAGS})
+            install(TARGETS ${ldc_name} DESTINATION ${CMAKE_INSTALL_PREFIX}/bin)
+        endmacro()
+        if (IS_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/ldc-profgen/ldc-profgen-${LLVM_VERSION_MAJOR}.${LLVM_VERSION_MINOR})
+            add_subdirectory(ldc-profgen/ldc-profgen-${LLVM_VERSION_MAJOR}.${LLVM_VERSION_MINOR})
+        else()
+            message(WARNING "ldc-profgen source not found (${CMAKE_CURRENT_SOURCE_DIR}/ldc-profgen/ldc-profgen-${LLVM_VERSION_MAJOR}.${LLVM_VERSION_MINOR})")
+        endif()
     endif()
 endif()