From dda8afcb9032b852b612971df2c116f916971c66 Mon Sep 17 00:00:00 2001 From: Andrew Kaster Date: Sun, 23 May 2021 14:20:22 -0600 Subject: [PATCH] Kernel: Add ENABLE_EXTRA_KERNEL_DEBUG_SYMBOLS option to set Og and ggdb3 When debugging kernel code, it's necessary to set extra flags. Normal advice is to set -ggdb3. Sometimes that still doesn't provide enough debugging information for complex functions that still get optimized. Compiling with -Og gives the best optimizations for debugging, but can sometimes be broken by changes that are innocuous when the compiler gets more of a chance to look at them. The new CMake option enables both compile options for kernel code. --- CMakeLists.txt | 1 + Documentation/BuildInstructions.md | 1 + Kernel/CMakeLists.txt | 7 ++++++- 3 files changed, 8 insertions(+), 1 deletion(-) diff --git a/CMakeLists.txt b/CMakeLists.txt index df038c2070b..f2fcdeea10a 100644 --- a/CMakeLists.txt +++ b/CMakeLists.txt @@ -22,6 +22,7 @@ option(ENABLE_KERNEL_ADDRESS_SANITIZER "Enable kernel address sanitizer testing option(ENABLE_MEMORY_SANITIZER "Enable memory sanitizer testing in gcc/clang" OFF) option(ENABLE_UNDEFINED_SANITIZER "Enable undefined behavior sanitizer testing in gcc/clang" OFF) option(ENABLE_FUZZER_SANITIZER "Enable fuzzer sanitizer testing in clang" OFF) +option(ENABLE_EXTRA_KERNEL_DEBUG_SYMBOLS "Enable -Og and -ggdb3 options for Kernel code for easier debugging" OFF) option(ENABLE_ALL_THE_DEBUG_MACROS "Enable all debug macros to validate they still compile" OFF) option(ENABLE_COMPILETIME_FORMAT_CHECK "Enable compiletime format string checks" ON) option(ENABLE_PCI_IDS_DOWNLOAD "Enable download of the pci.ids database at build time" ON) diff --git a/Documentation/BuildInstructions.md b/Documentation/BuildInstructions.md index dd5c70a2ccb..5a132b99f16 100644 --- a/Documentation/BuildInstructions.md +++ b/Documentation/BuildInstructions.md @@ -246,6 +246,7 @@ There are some optional features that can be enabled during compilation that are - `ENABLE_MEMORY_SANITIZER`: enables runtime checks for uninitialized memory accesses in Lagom test cases. - `ENABLE_UNDEFINED_SANITIZER`: builds in runtime checks for [undefined behavior](https://en.wikipedia.org/wiki/Undefined_behavior) (like null pointer dereferences and signed integer overflows) in Lagom test cases. - `ENABLE_FUZZER_SANITIZER`: builds [fuzzers](https://en.wikipedia.org/wiki/Fuzzing) for various parts of the system. +- `ENABLE_EXTRA_KERNEL_DEBUG_SYMBOLS`: sets -Og and -ggdb3 compile options for building the Kernel. Allows for easier debugging of Kernel code. By default, the Kernel is built with -Os instead. - `ENABLE_ALL_THE_DEBUG_MACROS`: used for checking whether debug code compiles on CI. This should not be set normally, as it clutters the console output and makes the system run very slowly. Instead, enable only the needed debug macros, as described below. - `ENABLE_COMPILETIME_FORMAT_CHECK`: checks for the validity of `std::format`-style format string during compilation. Enabled by default. - `ENABLE_PCI_IDS_DOWNLOAD`: downloads the [`pci.ids` database](https://pci-ids.ucw.cz/) that contains information about PCI devices at build time, if not already present. Enabled by default. diff --git a/Kernel/CMakeLists.txt b/Kernel/CMakeLists.txt index 02859fdbf03..1d7446c2745 100644 --- a/Kernel/CMakeLists.txt +++ b/Kernel/CMakeLists.txt @@ -1,4 +1,9 @@ -add_compile_options(-Os) +if (ENABLE_EXTRA_KERNEL_DEBUG_SYMBOLS) + add_compile_options(-Og) + add_compile_options(-ggdb3) +else() + add_compile_options(-Os) +endif() if ("${SERENITY_ARCH}" STREQUAL "i686") set(KERNEL_ARCH i386)