malloc hangs indefinitely

[Dave Hammond]

In a reasonably large project I am involved with, a call from fgetc()
to malloc() appears to hang indefinitely.  After killing the process
and running adb, a $C command shows:

* _malloc(0x408)	from __findbuf+0x3a
__findbuf(0x18825b8)	from __filbuf+0x17
__filbuf(0x18825b8)	from _fgetc+0x1e
_fgetc(0x18825b8)	from _U_CmdLex+0xde
_U_CmdLex(0x187e550)	from _f_newform+0x187
_f_newform(0x1883d0c, 0x373)	from _U_FrmRun+0x63
_U_FrmRun(0x1883d0c, 0x0, 0x0)	from _EX_Form+0x74
????????(0x1, 0x187e658)	from _U_UsrExec+0x56
_U_UsrExec(0x1,	0x187e658)	from _U_LocalExec+0x2b2
_U_LocalExec(0x1890910)	from _U_MnuCommand+0x103
_U_MnuCommand(0x1890910)	from _main+0x389
_main(0x0, 0x187eb4c, 0x187eb54)	from __start+0x39
__start()	from start0+0xc

My guess is that malloc is in an infinite loop looking for suitable
space in its heap.  Any suggestions on what might cause malloc to
spin its wheels?  Have I perhaps trashed malloc's heap list?

--
Dave Hammond
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