Add debug and LLVM asan build options

In addition, the default build now uses -O3 and has no debug symbols.
-Wmissing-field-initializer was removed due to false positives on
newer versions of clang.

INSTALL.md

@@ -59,6 +59,8 @@ Run `make doc` in the build directory after editing the asciidoc files to regene
   * `DISABLE_QRPNG` → Disable support for exporting QR as PNG
   * `DISABLE_DESKTOP_NOTIFY=1` → Disable desktop notifications support
   * `ENABLE_PYTHON=1` → Build toxic with Python scripting support
+  * `ENABLE_DEBUG=1` → Build toxic with debug symbols on and no compiler optimizations
+  * `ENABLE_ASAN=1` → Build toxic with LLVM Address Sanitizer enabled
 
 * `DESTDIR=""` Specifies the base install directory for binaries and data files (e.g.: DESTDIR="/tmp/build/pkg")
 

Makefile

@@ -5,8 +5,7 @@ CFG_DIR = $(BASE_DIR)/cfg
 
 LIBS = toxcore ncursesw libconfig libcurl
 
-CFLAGS ?= -g
-CFLAGS += -std=c99 -pthread -Wall -Wpedantic -Wunused -fstack-protector-all -Wvla -Wmissing-field-initializers -Wno-missing-braces
+CFLAGS = -std=c99 -pthread -Wall -Wpedantic -Wunused -fstack-protector-all -Wvla -Wno-missing-braces
 CFLAGS += '-DTOXICVER="$(VERSION)"' -DHAVE_WIDECHAR -D_XOPEN_SOURCE_EXTENDED -D_FILE_OFFSET_BITS=64
 CFLAGS += '-DPACKAGE_DATADIR="$(abspath $(DATADIR))"'
 CFLAGS += ${USER_CFLAGS}
@@ -18,6 +17,20 @@ OBJ += file_transfers.o friendlist.o global_commands.o conference_commands.o con
 OBJ += line_info.o log.o message_queue.o misc_tools.o name_lookup.o notify.o prompt.o qr_code.o settings.o
 OBJ += term_mplex.o toxic.o toxic_strings.o windows.o
 
+# Check if debug build is enabled
+DEBUG := $(shell if [ -z "$(DEBUG_ENABLED)" ] || [ "$(DEBUG_ENABLED)" = "0" ] ; then echo disabled ; else echo enabled ; fi)
+ifneq ($(DEBUG), disabled)
+	CFLAGS += -O0 -g -DDEBUG
+else
+	CFLAGS += -O3
+endif
+
+# Check if LLVM Address Sanitizer is enabled
+ASAN_ENABLED := $(shell if [ -z "$(ENABLE_ASAN)" ] || [ "$(ENABLE_ASAN)" = "0" ] ; then echo disabled ; else echo enabled ; fi)
+ifneq ($(ASAN_ENABLED), disabled)
+	CFLAGS += -fsanitize=address -fno-omit-frame-pointer
+endif
+
 # Check on wich system we are running
 UNAME_S = $(shell uname -s)
 ifeq ($(UNAME_S), Linux)

cfg/targets/help.mk

@@ -17,6 +17,8 @@ help:
 	@echo "  DISABLE_QRCODE:         Set to \"1\" to force building without QR export support"
 	@echo "  DISABLE_QRPNG:          Set to \"1\" to force building without QR exported as PNG support"
 	@echo "  ENABLE_PYTHON:          Set to \"1\" to enable building with Python scripting support"
+	@echo "  DEBUG_ENABLED:          Set to \"1\" to build with debug symbols on and no compiler optimizations"
+	@echo "  ASAN_ENABLED:           Set to \"1\" to build with LLVM address sanitizer enabled.
 	@echo "  USER_CFLAGS:            Add custom flags to default CFLAGS"
 	@echo "  USER_LDFLAGS:           Add custom flags to default LDFLAGS"
 	@echo "  PREFIX:                 Specify a prefix directory for binaries, data files,... (default is \"$(abspath $(PREFIX))\")"