| 1 | /* Example on weak aliasing as found in some GCC manual: | 
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| 2 | * http://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html | 
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| 3 | */ | 
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| 4 | #include <stdio.h> | 
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| 5 |  | 
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| 6 | /* GCC Style */ | 
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| 7 | int __f () | 
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| 8 | { | 
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| 9 | return 1; | 
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| 10 | } | 
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| 11 | int f () __attribute__ ((weak, alias ("__f"))); | 
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| 12 |  | 
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| 13 |  | 
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| 14 | /* SUN style */ | 
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| 15 | extern int WeakExternalWithLocalDefault_ResolveDefault(void); | 
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| 16 | int LocalDefault(void) | 
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| 17 | { | 
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| 18 | return 2; | 
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| 19 | } | 
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| 20 | #pragma weak WeakExternalWithLocalDefault_ResolveDefault = LocalDefault | 
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| 21 |  | 
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| 22 | extern int ExternalDefault(void); | 
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| 23 | extern int   WeakExternalWithExternalDefault_ResolveDefault(void); | 
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| 24 | #pragma weak WeakExternalWithExternalDefault_ResolveDefault = ExternalDefault | 
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| 25 |  | 
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| 26 | /* resolve weak external (still SUN style) */ | 
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| 27 | extern int   WeakExternalWithLocalDefault_ResolveWKEXT(void); | 
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| 28 | #pragma weak WeakExternalWithLocalDefault_ResolveWKEXT = LocalDefault | 
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| 29 |  | 
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| 30 | #if 0 /* BROKEN_GAS */ | 
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| 31 | extern int   WeakExternalWithExternalDefault_ResolveWKEXT(void); | 
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| 32 | #pragma weak WeakExternalWithExternalDefault_ResolveWKEXT = ExternalDefault | 
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| 33 | #endif | 
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| 34 |  | 
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| 35 |  | 
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| 36 | int main() | 
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| 37 | { | 
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| 38 | int rc = 0; | 
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| 39 | int i; | 
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| 40 |  | 
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| 41 | i = f(); | 
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| 42 | if (i != 1) | 
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| 43 | { | 
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| 44 | printf("weak3: f() returned %d expected %d\n", i, 1); | 
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| 45 | rc++; | 
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| 46 | } | 
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| 47 |  | 
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| 48 | i = WeakExternalWithLocalDefault_ResolveDefault(); | 
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| 49 | if (i != 2) | 
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| 50 | { | 
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| 51 | printf("weak3: WeakExternalWithLocalDefault_ResolveDefault() returned %d expected %d\n", i, 2); | 
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| 52 | rc++; | 
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| 53 | } | 
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| 54 |  | 
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| 55 | i = WeakExternalWithExternalDefault_ResolveDefault(); | 
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| 56 | if (i != -1) | 
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| 57 | { | 
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| 58 | printf("weak3: WeakExternalWithExternalDefault_ResolveDefault() returned %d expected %d\n", i, -1); | 
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| 59 | rc++; | 
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| 60 | } | 
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| 61 |  | 
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| 62 | i = WeakExternalWithLocalDefault_ResolveWKEXT(); | 
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| 63 | if (i != -2) | 
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| 64 | { | 
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| 65 | printf("weak3: WeakExternalWithLocalDefault_ResolveWKEXT() returned %d expected %d\n", i, -2); | 
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| 66 | rc++; | 
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| 67 | } | 
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| 68 |  | 
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| 69 | #if 0 /* BROKEN_GAS */ | 
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| 70 | i = WeakExternalWithExternalDefault_ResolveWKEXT(); | 
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| 71 | if (i != -3) | 
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| 72 | { | 
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| 73 | printf("weak3: WeakExternalWithExternalDefault_ResolveWKEXT() returned %d expected %d\n", i, -3); | 
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| 74 | rc++; | 
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| 75 | } | 
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| 76 | #endif | 
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| 77 |  | 
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| 78 | return rc; | 
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| 79 | } | 
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