[xen master] tools: Workaround wrong use of tools/Rules.mk by qemu-trad

[patchbot@xxxxxxx]

commit cc4747be8ba157a3b310921e9ee07fb8545aa206
Author:     Anthony PERARD <anthony.perard@xxxxxxxxxx>
AuthorDate: Mon Oct 17 11:34:03 2022 +0100
Commit:     Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
CommitDate: Mon Oct 17 14:57:34 2022 +0100

    tools: Workaround wrong use of tools/Rules.mk by qemu-trad
    
    qemu-trad build system, when built from xen.git, will make use of
    Rules.mk (setup via qemu-trad.git/xen-setup). This mean that changes
    to Rules.mk will have an impact our ability to build qemu-trad.
    
    Recent commit e4f5949c4466 ("tools: Add -Werror by default to all
    tools/") have added "-Werror" to the CFLAGS and qemu-trad start to use
    it. But this fails and there's lots of warning that are now turned
    into error.
    
    We should teach qemu-trad and xen.git to not have to use Rules.mk when
    building qemu-trad, but for now, avoid adding -Werror to CFLAGS when
    building qemu-trad.
    
    Signed-off-by: Anthony PERARD <anthony.perard@xxxxxxxxxx>
    Acked-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
    Release-acked-by: Henry Wang <Henry.Wang@xxxxxxx>
---
 tools/Makefile | 1 +
 tools/Rules.mk | 3 +++
 2 files changed, 4 insertions(+)

diff --git a/tools/Makefile b/tools/Makefile
index 0c1d8b64a4..9e28027835 100644
--- a/tools/Makefile
+++ b/tools/Makefile
@@ -159,6 +159,7 @@ qemu-traditional-recurse = \
        set -e; \
                $(buildmakevars2shellvars); \
                export CONFIG_BLKTAP1=n; \
+               export BUILDING_QEMU_TRAD=y; \
                cd qemu-xen-traditional-dir; \
                $(1)
 
diff --git a/tools/Rules.mk b/tools/Rules.mk
index 34d495fff7..6e135387bd 100644
--- a/tools/Rules.mk
+++ b/tools/Rules.mk
@@ -141,9 +141,12 @@ endif
 
 CFLAGS_libxenlight += $(CFLAGS_libxenctrl)
 
+# Don't add -Werror if we are used by qemu-trad build system.
+ifndef BUILDING_QEMU_TRAD
 ifeq ($(CONFIG_WERROR),y)
 CFLAGS += -Werror
 endif
+endif
 
 ifeq ($(debug),y)
 # Use -Og if available, -O0 otherwise
--
generated by git-patchbot for /home/xen/git/xen.git#master