configure: Add -Wno-psabi

On aarch64, gcc 9.3 is generating

qemu/exec.c: In function ‘address_space_translate_iommu’:
qemu/exec.c:431:28: note: parameter passing for argument of type \
  ‘MemTxAttrs’ {aka ‘struct MemTxAttrs’} changed in GCC 9.1

and many other repetitions.  This structure, and the functions
amongst which it is passed, are not part of a QEMU public API.
Therefore we do not care how the compiler passes the argument,
so long as the compiler is self-consistent.

The only portion of QEMU which does have a public api, and so
must have a stable abi, is "qemu/plugin.h".  We test this by
forcing -Wpsabi in tests/plugin/Makefile.

Buglink: https://bugs.launchpad.net/qemu/+bug/1881552
Reviewed-by: Alex Bennée <[email protected]>
Reviewed-by: Philippe Mathieu-Daudé <[email protected]>
Signed-off-by: Richard Henderson <[email protected]>
Message-id: [email protected]
Signed-off-by: Peter Maydell <[email protected]>

Author: rth7680

configure

@@ -2055,6 +2055,7 @@ add_to nowarn_flags -Wno-shift-negative-value
 add_to nowarn_flags -Wno-string-plus-int
 add_to nowarn_flags -Wno-typedef-redefinition
 add_to nowarn_flags -Wno-tautological-type-limit-compare
+add_to nowarn_flags -Wno-psabi
 
 gcc_flags="$warn_flags $nowarn_flags"
 

tests/plugin/Makefile

@@ -17,7 +17,7 @@ NAMES += lockstep
 
 SONAMES := $(addsuffix .so,$(addprefix lib,$(NAMES)))
 
-QEMU_CFLAGS += -fPIC
+QEMU_CFLAGS += -fPIC -Wpsabi
 QEMU_CFLAGS += -I$(SRC_PATH)/include/qemu
 
 all: $(SONAMES)