[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Qemu-devel] [PATCH for-1.6?] tpm.c: Don't try to put -1 in a variable o
From: |
Peter Maydell |
Subject: |
[Qemu-devel] [PATCH for-1.6?] tpm.c: Don't try to put -1 in a variable of type TpmModel |
Date: |
Mon, 29 Jul 2013 12:22:11 +0100 |
The TpmModel type is an enum (valid values 0 and 1), which means
the compiler can legitimately decide that comparisons like
'tpm_models[i] == -1' are never true. (For example it could
pick 'unsigned char' as its type for representing the enum.)
Avoid this issue by using TPM_MODEL_MAX to mark entries in
the tpm_models[] array which aren't filled in, instead of -1.
This silences a clang warning:
tpm.c:43:27: error: comparison of constant -1 with expression of type
'enum TpmModel' is always false
[-Werror,-Wtautological-constant-out-of-range-compare]
if (tpm_models[i] == -1) {
~~~~~~~~~~~~~ ^ ~~
Signed-off-by: Peter Maydell <address@hidden>
---
Disclaimer: I have compiled this, and it's a pretty safe looking
change, but I haven't tested it...
tpm.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/tpm.c b/tpm.c
index f13c9bc..d68d69f 100644
--- a/tpm.c
+++ b/tpm.c
@@ -32,7 +32,7 @@ static TPMDriverOps const *be_drivers[TPM_MAX_DRIVERS] = {
};
static enum TpmModel tpm_models[TPM_MAX_MODELS] = {
- -1,
+ TPM_MODEL_MAX,
};
int tpm_register_model(enum TpmModel model)
@@ -40,7 +40,7 @@ int tpm_register_model(enum TpmModel model)
int i;
for (i = 0; i < TPM_MAX_MODELS; i++) {
- if (tpm_models[i] == -1) {
+ if (tpm_models[i] == TPM_MODEL_MAX) {
tpm_models[i] = model;
return 0;
}
--
1.7.9.5
- [Qemu-devel] [PATCH for-1.6?] tpm.c: Don't try to put -1 in a variable of type TpmModel,
Peter Maydell <=