Add a new knob WITH_DEBUG_FILES to control the building of standalone

debug files for userland programs and libraries.  The "-g" debug flag
is automatically applied when WITH_DEBUG_FILES is set.

The debug files are now named ${prog}.debug and ${shlib}.debug for
consistency with other systems and documentation.  In addition they are
installed under /usr/lib/debug, to simplify the process of installing
them if needed after a crash.  Users of bsd.{prog,lib}.mk outside of the
base system place the standalone debug files in a .debug subdirectory.
GDB automatically searches both of these directories for standalone
debug files.

Thanks to everyone who contributed changes, review, and testing during
development.

4 files changed, 98 insertions, 17 deletions

diff --git a/share/mk/bsd.crunchgen.mk b/share/mk/bsd.crunchgen.mk
index 95f1aa3..d8f07b1 100644
--- a/share/mk/bsd.crunchgen.mk
+++ b/share/mk/bsd.crunchgen.mk
@@ -47,6 +47,9 @@ CRUNCH_GENERATE_LINKS?=	yes
 
 CLEANFILES+= $(CONF) *.o *.lo *.c *.mk *.cache *.a *.h
 
+# Don't try to extract debug info from ${PROG}.
+NO_DEBUG_FILES=
+
 # Program names and their aliases contribute hardlinks to 'rescue' executable,
 # except for those that get suppressed.
 .for D in $(CRUNCH_SRCDIRS)
diff --git a/share/mk/bsd.lib.mk b/share/mk/bsd.lib.mk
index cb2544c..3edb5bc 100644
--- a/share/mk/bsd.lib.mk
+++ b/share/mk/bsd.lib.mk
@@ -43,6 +43,12 @@ CTFFLAGS+= -g
 STRIP?=	-s
 .endif
 
+.if ${MK_DEBUG_FILES} != "no" && empty(DEBUG_FLAGS:M-g) && \
+    empty(DEBUG_FLAGS:M-gdwarf*)
+CFLAGS+= -g
+CTFFLAGS+= -g
+.endif
+
 .include <bsd.libnames.mk>
 
 # prefer .s to a .c, add .po, remove stuff not used in the BSD libraries
@@ -114,8 +120,17 @@ PO_FLAG=-pg
 all: objwarn
 
 .if defined(SHLIB_NAME)
-.if defined(DEBUG_FLAGS)
-SHLIB_NAME_FULL=${SHLIB_NAME}.debug
+.if ${MK_DEBUG_FILES} != "no"
+SHLIB_NAME_FULL=${SHLIB_NAME}.full
+# Use ${DEBUGDIR} for base system debug files, else .debug subdirectory
+.if ${SHLIBDIR} == "/boot" ||\
+    ${SHLIBDIR:C%/lib(/.*)?$%/lib%} == "/lib" ||\
+    ${SHLIBDIR:C%/usr/lib(32)?(/.*)?%/usr/lib%} == "/usr/lib"
+DEBUGFILEDIR=${DEBUGDIR}${SHLIBDIR}
+.else
+DEBUGFILEDIR=${SHLIBDIR}/.debug
+DEBUGMKDIR=
+.endif
 .else
 SHLIB_NAME_FULL=${SHLIB_NAME}
 .endif
@@ -201,13 +216,13 @@ ${SHLIB_NAME_FULL}: ${SOBJS}
 	${CTFMERGE} ${CTFFLAGS} -o ${.TARGET} ${SOBJS}
 .endif
 
-.if defined(DEBUG_FLAGS)
-CLEANFILES+=	${SHLIB_NAME_FULL} ${SHLIB_NAME}.symbols
-${SHLIB_NAME}: ${SHLIB_NAME_FULL} ${SHLIB_NAME}.symbols
-	${OBJCOPY} --strip-debug --add-gnu-debuglink=${SHLIB_NAME}.symbols \
+.if ${MK_DEBUG_FILES} != "no"
+CLEANFILES+=	${SHLIB_NAME_FULL} ${SHLIB_NAME}.debug
+${SHLIB_NAME}: ${SHLIB_NAME_FULL} ${SHLIB_NAME}.debug
+	${OBJCOPY} --strip-debug --add-gnu-debuglink=${SHLIB_NAME}.debug \
 	    ${SHLIB_NAME_FULL} ${.TARGET}
 
-${SHLIB_NAME}.symbols: ${SHLIB_NAME_FULL}
+${SHLIB_NAME}.debug: ${SHLIB_NAME_FULL}
 	${OBJCOPY} --only-keep-debug ${SHLIB_NAME_FULL} ${.TARGET}
 .endif
 .endif #defined(SHLIB_NAME)
@@ -286,10 +301,13 @@ _libinstall:
 	${INSTALL} ${STRIP} -o ${LIBOWN} -g ${LIBGRP} -m ${LIBMODE} \
 	    ${_INSTALLFLAGS} ${_SHLINSTALLFLAGS} \
 	    ${SHLIB_NAME} ${DESTDIR}${SHLIBDIR}
-.if defined(DEBUG_FLAGS)
-	${INSTALL} -o ${LIBOWN} -g ${LIBGRP} -m ${LIBMODE} \
+.if ${MK_DEBUG_FILES} != "no"
+.if defined(DEBUGMKDIR)
+	${INSTALL} -T debug -d ${DESTDIR}${DEBUGFILEDIR}
+.endif
+	${INSTALL} -T debug -o ${LIBOWN} -g ${LIBGRP} -m ${DEBUGMODE} \
 	    ${_INSTALLFLAGS} \
-	    ${SHLIB_NAME}.symbols ${DESTDIR}${SHLIBDIR}
+	    ${SHLIB_NAME}.debug ${DESTDIR}${DEBUGFILEDIR}
 .endif
 .if defined(SHLIB_LINK)
 # ${_SHLIBDIRPREFIX} and ${_LDSCRIPTROOT} are both needed when cross-building
diff --git a/share/mk/bsd.own.mk b/share/mk/bsd.own.mk
index dfa8ed6..a9eee61 100644
--- a/share/mk/bsd.own.mk
+++ b/share/mk/bsd.own.mk
@@ -43,6 +43,11 @@
 # LIBMODE	Library mode. [${NOBINMODE}]
 #
 #
+# DEBUGDIR	Base path for standalone debug files. [/usr/lib/debug]
+#
+# DEBUGMODE	Mode for debug files. [${NOBINMODE}]
+#
+#
 # KMODDIR	Base path for loadable kernel modules
 #		(see kld(4)). [/boot/kernel]
 #
@@ -147,6 +152,9 @@ LIBOWN?=	${BINOWN}
 LIBGRP?=	${BINGRP}
 LIBMODE?=	${NOBINMODE}
 
+DEBUGDIR?=	/usr/lib/debug
+DEBUGMODE?=	${NOBINMODE}
+
 
 # Share files
 SHAREDIR?=	/usr/share
@@ -213,6 +221,7 @@ COMPRESS_EXT?=	.gz
 #
 .for var in \
     CTF \
+    DEBUG_FILES \
     INSTALLLIB \
     MAN \
     PROFILE
@@ -365,6 +374,7 @@ __DEFAULT_NO_OPTIONS = \
     BSD_GREP \
     CLANG_EXTRAS \
     CTF \
+    DEBUG_FILES \
     GPL_DTC \
     HESIOD \
     ICONV \
diff --git a/share/mk/bsd.prog.mk b/share/mk/bsd.prog.mk
index 0991915..f4546dc 100644
--- a/share/mk/bsd.prog.mk
+++ b/share/mk/bsd.prog.mk
@@ -24,8 +24,24 @@ CTFFLAGS+= -g
 .endif
 .endif
 
+.if defined(PROG_CXX)
+PROG=	${PROG_CXX}
+.endif
+
+.if defined(PROG) && target(${PROG})
+MK_DEBUG_FILES=	no
+.elif !empty(LDFLAGS:M-Wl,*--oformat,*) || !empty(LDFLAGS:M-static)
+MK_DEBUG_FILES=	no
+.endif
+
 .if defined(CRUNCH_CFLAGS)
 CFLAGS+=${CRUNCH_CFLAGS}
+.else
+.if ${MK_DEBUG_FILES} != "no" && empty(DEBUG_FLAGS:M-g) && \
+    empty(DEBUG_FLAGS:M-gdwarf-*)
+CFLAGS+= -g
+CTFFLAGS+= -g
+.endif
 .endif
 
 .if !defined(DEBUG_FLAGS)
@@ -36,21 +52,36 @@ STRIP?=	-s
 LDFLAGS+= -static
 .endif
 
-.if defined(PROG_CXX)
-PROG=	${PROG_CXX}
+.if ${MK_DEBUG_FILES} != "no"
+PROG_FULL=${PROG}.full
+# Use ${DEBUGDIR} for base system debug files, else .debug subdirectory
+.if defined(BINDIR) && (\
+    ${BINDIR} == "/bin" ||\
+    ${BINDIR} == "/libexec" ||\
+    ${BINDIR} == "/sbin" ||\
+    ${BINDIR:C%/usr/(bin|bsdinstall|games|libexec|lpr|sendmail|sm.bin|sbin)(/.*)?%/usr/bin%} == "/usr/bin"\
+     )
+DEBUGFILEDIR=	${DEBUGDIR}${BINDIR}
+.else
+DEBUGFILEDIR?=	${BINDIR}/.debug
+DEBUGMKDIR=
+.endif
+.else
+PROG_FULL=	${PROG}
 .endif
 
 .if defined(PROG)
 PROGNAME?=	${PROG}
+
 .if defined(SRCS)
 
 OBJS+=  ${SRCS:N*.h:R:S/$/.o/g}
 
 .if target(beforelinking)
 beforelinking: ${OBJS}
-${PROG}: beforelinking
+${PROG_FULL}: beforelinking
 .endif
-${PROG}: ${OBJS}
+${PROG_FULL}: ${OBJS}
 .if defined(PROG_CXX)
 	${CXX} ${CXXFLAGS} ${LDFLAGS} -o ${.TARGET} ${OBJS} ${LDADD}
 .else
@@ -78,9 +109,9 @@ OBJS+=	${PROG}.o
 
 .if target(beforelinking)
 beforelinking: ${OBJS}
-${PROG}: beforelinking
+${PROG_FULL}: beforelinking
 .endif
-${PROG}: ${OBJS}
+${PROG_FULL}: ${OBJS}
 .if defined(PROG_CXX)
 	${CXX} ${CXXFLAGS} ${LDFLAGS} -o ${.TARGET} ${OBJS} ${LDADD}
 .else
@@ -89,10 +120,19 @@ ${PROG}: ${OBJS}
 .if ${MK_CTF} != "no"
 	${CTFMERGE} ${CTFFLAGS} -o ${.TARGET} ${OBJS}
 .endif
-.endif
+.endif # !target(${PROG})
 
 .endif # !defined(SRCS)
 
+.if ${MK_DEBUG_FILES} != "no"
+${PROG}: ${PROG_FULL} ${PROGNAME}.debug
+	${OBJCOPY} --strip-debug --add-gnu-debuglink=${PROGNAME}.debug \
+	    ${PROG_FULL} ${.TARGET}
+
+${PROGNAME}.debug: ${PROG_FULL}
+	${OBJCOPY} --only-keep-debug ${PROG_FULL} ${.TARGET}
+.endif
+
 .if	${MK_MAN} != "no" && !defined(MAN) && \
 	!defined(MAN1) && !defined(MAN2) && !defined(MAN3) && \
 	!defined(MAN4) && !defined(MAN5) && !defined(MAN6) && \
@@ -109,6 +149,9 @@ all: _manpages
 
 .if defined(PROG)
 CLEANFILES+= ${PROG}
+.if ${MK_DEBUG_FILES} != "no"
+CLEANFILES+=	${PROG_FULL} ${PROGNAME}.debug
+.endif
 .endif
 
 .if defined(OBJS)
@@ -156,6 +199,13 @@ _proginstall:
 .if defined(PROG)
 	${INSTALL} ${STRIP} -o ${BINOWN} -g ${BINGRP} -m ${BINMODE} \
 	    ${_INSTALLFLAGS} ${PROG} ${DESTDIR}${BINDIR}/${PROGNAME}
+.if ${MK_DEBUG_FILES} != "no"
+.if defined(DEBUGMKDIR)
+	${INSTALL} -T debug -d ${DESTDIR}${DEBUGFILEDIR}
+.endif
+	${INSTALL} -T debug -o ${BINOWN} -g ${BINGRP} -m ${DEBUGMODE} \
+	    ${PROGNAME}.debug ${DESTDIR}${DEBUGFILEDIR}/${PROGNAME}.debug
+.endif
 .endif
 .endif	# !target(realinstall)