revert changes to when -nostartfiles is specified in link for 1.5.1 as it can...

revert changes to when -nostartfiles is specified in link for 1.5.1 as it can cause link errors with C++; see #1368

src/rp2_common/pico_standard_link/CMakeLists.txt

@@ -74,11 +74,9 @@ if (NOT TARGET pico_standard_link)
         target_compile_definitions(pico_standard_link INTERFACE PICO_DEOPTIMIZED_DEBUG=1)
     endif()
 
-    # -nostartfiles will be added if not using C++ exceptions (which is the only thing that seems to need it)
-    if (PICO_C_COMPILER_IS_GNU AND NOT PICO_CXX_ENABLE_EXCEPTIONS)
-#        target_link_options(pico_standard_link INTERFACE $<$<IF:$<STREQUAL:$<TARGET_PROPERTY:PICO_TARGET_BINARY_TYPE>,no_flash>,1,$<AND:$<BOOL:${PICO_NO_FLASH}>,$<STREQUAL:,$<TARGET_PROPERTY:PICO_TARGET_BINARY_TYPE>>>>:-nostartfiles>)
-        target_link_options(pico_standard_link INTERFACE -nostartfiles)
-    endif()
+    # this (arguably wrong) code is restored for 1.5.1 as setting -nostartfiles on many C++ binaries causes link errors. see issue #1368
+    # -nostartfiles will be added if PICO_NO_FLASH would be defined to 1
+    target_link_options(pico_standard_link INTERFACE $<$<IF:$<STREQUAL:$<TARGET_PROPERTY:PICO_TARGET_BINARY_TYPE>,no_flash>,1,$<AND:$<BOOL:${PICO_NO_FLASH}>,$<STREQUAL:,$<TARGET_PROPERTY:PICO_TARGET_BINARY_TYPE>>>>:-nostartfiles>)
     # boot_stage2 will be linked if PICO_NO_FLASH would be defined to 0
     target_link_libraries(pico_standard_link INTERFACE $<$<NOT:$<IF:$<STREQUAL:$<TARGET_PROPERTY:PICO_TARGET_BINARY_TYPE>,no_flash>,1,$<AND:$<BOOL:${PICO_NO_FLASH}>,$<STREQUAL:,$<TARGET_PROPERTY:PICO_TARGET_BINARY_TYPE>>>>>:$<IF:$<BOOL:$<TARGET_PROPERTY:PICO_TARGET_BOOT_STAGE2>>,$<TARGET_PROPERTY:PICO_TARGET_BOOT_STAGE2>,bs2_default>_library>)