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Tags More Cancel. Error: call to undefined method stdclass::language 0. Cannot find symbol variables error on java. Error:undefined referrence to the function. Layout: fixed fluid. Web03 2. Strip HTML. Encode HTML. Paste as-is. Code block. Quoted Text. Best guess. Optional Password. A self-contained shared object, in which all references to external symbols are satisfied by named dependencies, provides maximum flexibility.
The shared object can be employed by many users without those users having to determine and establish dependencies to satisfy the shared object's requirements. Weak symbol references that remain unresolved, do not result in a fatal error condition, no matter what output file type is being generated. If a static executable is being generated, the symbol is converted to an absolute symbol with an assigned value of zero.
If a dynamic executable or shared object is being produced, the symbol is left as an undefined weak reference with an assigned value of zero. During process execution, the runtime linker searches for this symbol. If the runtime linker does not find a match, the reference is bound to an address of zero instead of generating a fatal relocation error. Historically, these undefined weak referenced symbols have been employed as a mechanism to test for the existence of functionality.
For example, the following C code fragment might have been used in the shared object libfoo. When building an application that references libfoo. If during execution of the application the function address tests nonzero, the function is called.
However, if the symbol definition is not found, the function address tests zero and therefore is not called. Compilation systems view this address comparison technique as having undefined semantics, which can result in the test statement being removed under optimization.
Active 3 years, 11 months ago. Viewed k times. Wolf 8, 7 7 gold badges 53 53 silver badges 97 97 bronze badges. Ant's Ant's And here is some speculation why about why libm isn't linked by default even though it contains part of the standard library: stackoverflow.
It's a duplicate to this one: stackoverflow. Is there a reason this doesn't throw an error when using an integer literal? Is the compiler doing the math? Add a comment. Active Oldest Votes. You need to link the with the -lm linker option You need to compile as gcc test.
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