git: 47363e99d3d3 - main - Enable compressed debug on little-endian targets

[Ed Maste]

The branch main has been updated by emaste:

URL: https://cgit.FreeBSD.org/src/commit/?id=47363e99d3d312c510902b68d5cf3094ddc7bb76

commit 47363e99d3d312c510902b68d5cf3094ddc7bb76
Author:     Ed Maste <emaste at FreeBSD.org>
AuthorDate: 2021-08-07 14:46:07 +0000
Commit:     Ed Maste <emaste at FreeBSD.org>
CommitDate: 2021-08-08 17:31:28 +0000

    Enable compressed debug on little-endian targets
    
    Compressed debug was enabled by default in commit c910570e7573, but
    broke the build on big-endian targets, and so was disabled in
    89ed2ecb14ce.
    
    Older versions of LLD fail with big-endian compressed debug sections.
    This was fixed in LLD upstream (commit c6ebc651b6fa) and merged to
    FreeBSD main (commit d69d07569ee2) by dim.
    
    External toolchains (e.g. the llvm12 package) will not yet have the fix.
    These may be used to link against base system .a archives, so compressed
    debug sections would cause trouble even though the base system is fixed.
    
    Enable compressed debug sections again, for little-endian targets only.
    As discussed on freebsd-hackers[1] I expect to undo this in the future
    (using compressed debug everywhere), once fixed versions of lld are
    widely available.
    
    Note that to be pedantically correct we should check both the compiler
    and the linker for compressed debug support, but given the external
    toolchain constraint the extra complexity does not seem worthwhile.
    
    [1] https://lists.freebsd.org/archives/freebsd-hackers/2021-August/000188.html
    
    PR:             257638
    Reported by:    jrtc27 [impact of .a archives]
    Discussed with: imp
    Relnotes:       Yes
    Sponsored by:   The FreeBSD Foundation
    Differential Revision:  https://reviews.freebsd.org/D31454
    
    Revert "Disable compressed debug by default"
    
    This reverts commit 89ed2ecb14ceabc27883282cf96559a9e7d52717.
---
 share/mk/bsd.compiler.mk | 9 ++++++++-
 share/mk/bsd.sys.mk      | 2 +-
 2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/share/mk/bsd.compiler.mk b/share/mk/bsd.compiler.mk
index 681f6ffec14c..757361a566dd 100644
--- a/share/mk/bsd.compiler.mk
+++ b/share/mk/bsd.compiler.mk
@@ -235,7 +235,14 @@ ${X_}COMPILER_FEATURES+=		c++11 c++14
 ${X_}COMPILER_FEATURES+=	c++17
 .endif
 .if ${${X_}COMPILER_TYPE} == "clang"
-${X_}COMPILER_FEATURES+=	compressed-debug retpoline init-all
+${X_}COMPILER_FEATURES+=	retpoline init-all
+# PR257638 lld fails with BE compressed debug.  Fixed in main but external tool
+# chains will initially not have the fix.  For now limit the feature to LE
+# targets.
+.include <bsd.endian.mk>
+.if ${TARGET_ENDIANNESS} == "1234"
+${X_}COMPILER_FEATURES+=	compressed-debug
+.endif
 .endif
 .if ${${X_}COMPILER_TYPE} == "clang" && ${${X_}COMPILER_VERSION} >= 100000 || \
 	(${${X_}COMPILER_TYPE} == "gcc" && ${${X_}COMPILER_VERSION} >= 80100)
diff --git a/share/mk/bsd.sys.mk b/share/mk/bsd.sys.mk
index 031d49bbaca2..a964cf6e596c 100644
--- a/share/mk/bsd.sys.mk
+++ b/share/mk/bsd.sys.mk
@@ -247,7 +247,7 @@ CFLAGS+=	${SSP_CFLAGS}
 
 # Additional flags passed in CFLAGS and CXXFLAGS when MK_DEBUG_FILES is
 # enabled.
-DEBUG_FILES_CFLAGS?= -g
+DEBUG_FILES_CFLAGS?= -g -gz=zlib
 
 # Allow user-specified additional warning flags, plus compiler and file
 # specific flag overrides, unless we've overridden this...