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> Yes, I think it was gcc-3.4.1 optimizing a bit much. > Here's a workaround backported from cvs to glibc-2.3.2: > Hi, I had those patches applied - however, it did not affect the file (malloc.c) that I was compiling. I did have compile optimization at -O0, though, which should disable no-unit-at-a-time completely. Just to make sure, I compiled the file (malloc/malloc.c) with -O0 -fno-unit-at-a-time explicitly, and the results were the same. The thing that was baffling me was that a nearly identical piece of code was generated correctly in the same file. I fianlly tracked it down to the multiple different ways glibc declares weak references: /* used by __pthread_initialize in glibc - works fine */ extern void __weak_one(void) __attribute__ ((weak)); /* works with gcc-3.4.1 IF used... */ extern void __weak_two (void); #pragma weak __weak_two /* used by __pthread_mutex_init in glibc (for mips at least) BAD in gcc-3.4.1 ! */ extern void __weak_three (void); asm(".weak " "__weak_three"); I'm assuming the problem is a 'trivial' dead code removal optimization - since gcc doesn't know anything about the contect of the "asm()" statement, if assumes that the "__weak_three" symbol is non-zero, and optimized out a check like "if (__weak_three != NULL)" I noticed that glibc-2.3.2 has a more complicated system for declaring weak references - I will test this with it when I get the chance... Will also put together a patch for glibc-2.2.5 to use #pragma instead of asm() (since I've been using 2.2.5 previously, and am not sure I want to upgrade yet...) -Jake ------ Want more information? See the CrossGCC FAQ, http://www.objsw.com/CrossGCC/ Want to unsubscribe? Send a note to crossgcc-unsubscribe@sources.redhat.com
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