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62 lines
1.3 KiB
C++
62 lines
1.3 KiB
C++
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#include "Test.h"
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/*
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This test case is intended to check for one particular binutils/xcoff problem:
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Without a patch, GNU ld fails to allocate space for weak uninitialized csects [BS],
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and therefore puts both at the same address.
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Minimal example:
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.weak _one[BS]
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.csect _one[BS]
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_one:
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.space 4
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.weak _two[BS]
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.csect _two[BS]
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_two:
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.space 4
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powerpc-apple-macos-as test.s > test.o
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powerpc-apple-macos-ld -r test.o -o linked.o
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powerpc-apple-macos-objdump -t -h linked.o
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Observe the size of the .bss section and the addresses of symbols _one and _two.
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This test case tests for it using a thread-safe local static variable in an inline
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function, which boils down to a pair of weakly-linked uninitialized csects as above.
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*/
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// noinline so that it doesn't get optimized away
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__attribute__((noinline)) int foo()
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{
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return 42;
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}
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// the `inline` triggers a problem.
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// the static var and its guard variable are marked `.weak`,
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// and the XCOFF linker puts them at the same address.
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inline int bar()
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{
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static int cachedFoo = foo();
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return cachedFoo;
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}
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// wrap it in a noinline function to make reading the assembly easier.
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__attribute__((noinline)) int baz()
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{
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return bar();
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}
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int main()
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{
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if (baz() != 42)
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TestLog("NO");
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else
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TestLog("OK");
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}
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