[Qemu-devel] [RFC PATCH 29/34] arm: cpu: Multi-define guard deep CPU specifics

[Peter Crosthwaite]

If MMU_USER_IDX or ENV_OFFSET is already defined, undefine it.
The undef will cause a compile error on the ambiguous case where
multiple cpu.h's are included yet either of these defs
is needed. This shouldn't happen, as the multi-include should only
happen in device-land system level code that need CPU defs from
multiple arches - e.g. a machine model with two different arch CPUs.
Such device code has no bussiness using MMU_USER_IDX or ENV_OFFSET.

ENV_GET_CPU s also multi-guarded to perform no action on second define.
This is for multi-arch where target-multi provides a working
implementation already

Signed-off-by: Peter Crosthwaite <address@hidden>
---
 target-arm/cpu-qom.h | 7 +++++++
 target-arm/cpu.h     | 5 +++++
 2 files changed, 12 insertions(+)

diff --git a/target-arm/cpu-qom.h b/target-arm/cpu-qom.h
index ed5a644..ad742ed 100644
--- a/target-arm/cpu-qom.h
+++ b/target-arm/cpu-qom.h
@@ -188,9 +188,16 @@ static inline ARMCPU *arm_env_get_cpu(CPUARMState *env)
     return container_of(env, ARMCPU, env);
 }
 
+#ifndef ENV_GET_CPU
 #define ENV_GET_CPU(e) CPU(arm_env_get_cpu(e))
+#endif
 
+#ifndef ENV_OFFSET
 #define ENV_OFFSET offsetof(ARMCPU, env)
+#else
+/* Try and cause a compile bug on any (invalid) users of the multiple def */
+#undef ENV_OFFSET
+#endif
 
 #ifndef CONFIG_USER_ONLY
 extern const struct VMStateDescription vmstate_arm_cpu;
diff --git a/target-arm/cpu.h b/target-arm/cpu.h
index e0363a2..53a8051 100644
--- a/target-arm/cpu.h
+++ b/target-arm/cpu.h
@@ -1627,7 +1627,12 @@ typedef enum ARMMMUIdx {
     ARMMMUIdx_S1NSE1 = 8,
 } ARMMMUIdx;
 
+#ifdef MMU_USER_IDX
+/* Try and cause a compile bug on any (invalid) users of the multiple def */
+#undef MMU_USER_IDX
+#else
 #define MMU_USER_IDX 0
+#endif
 
 /* Return the exception level we're running at if this is our mmu_idx */
 static inline int arm_mmu_idx_to_el(ARMMMUIdx mmu_idx)
-- 
1.9.1